We thank Dr. John Greaves and Ms. Soroosh Sorooshian, Department of Chemistry, University of California, Irvine Mass Spectrometry Facility, for mass spectrometric analyses. We also thank Mr. Jacob Buchanan for helpful discussions, as well as Miss Stephanie J. Conn, Mrs. Shannon M. Huffman (Vreeland), and Miss Alexandra N. Wexler for early stage work on this project. Partial funding was provided by the Central Washington University (CWU) School of Graduate Studies (C.E.M), the CWU Seed Grant Program, and the CWU Faculty Research Program.

<ol>
	<li>Adabala, P. J. P., Legresley, E. B., Bance, N., Niikura, M., Pinto, B. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exploitation+of+the+Catalytic+Site+and+150+Cavity+for+Design+of+Influenza+A+Neuraminidase+Inhibitors.">Exploitation of the Catalytic Site and 150 Cavity for Design of Influenza A Neuraminidase Inhibitors.</a> J. Org. Chem. 78 (21), 10867-10877 (2013).</li><li>Trost, B. M., Kaneko, T., Andersen, N. G., Tappertzhofen, C., Fahr, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Total+Synthesis+of+Aeruginosin+98B.">Total Synthesis of Aeruginosin 98B.</a> J. Am. Chem. Soc. 134 (46), 18944-18947 (2012).</li><li>Conn, S. J., Vreeland, S. M., Wexler, A. N., Pouwer, R. H., Quinn, R. J., Chamberland, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Total+Synthesis+of+Clavatadine.">Total Synthesis of Clavatadine.</a> A. J. Nat. Prod. 78, 120-124 (2014).</li><li>Buchanan, J. C., Petersen, B. P., Chamberland, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Concise+Total+Synthesis+of+Phidianidine+A+and+B.">Concise Total Synthesis of Phidianidine A and B.</a> Tetrahedron Lett. 54, 6002-6004 (2013).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Technical Bulletin AL-134: Handling Air-Sensitive Reagents. , (2012).</li><li>Castagnolo, D., Raffi, F., Giorgi, G., Botta, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macrocyclization+of+Di-Boc-guanidino-alkylamines+Related+to+Guazatine+Components:+Discovery+and+Synthesis+of+Innovative+Macrocyclic+Amidinoureas.">Macrocyclization of Di-Boc-guanidino-alkylamines Related to Guazatine Components: Discovery and Synthesis of Innovative Macrocyclic Amidinoureas.</a> Eur. J. Org. Chem. 2009 (3), 334-337 (2009).</li><li>Zubrick, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Organic Chem Lab Survival Manual: A Student's Guide to Techniques. , (2012).</li><li>Pirrung, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Synthetic Organic Chemist's Companion. , (2007).</li><li>Padias, A. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Making the Connections 2: A How-To Guide for Organic Chemistry Lab Techniques, Second Edition. , (2011).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Digital Lab Techniques Manual: Volumetric Techniques. , (2007).</li><li>Baker, T. J., Tomioka, M., Goodman, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+and+Use+of+N,N'-Di-Boc-N&amp;#34;-Triflylguanidine.">Preparation and Use of N,N'-Di-Boc-N&amp;#34;-Triflylguanidine.</a> Org. Synth. 78, 91-98 (2002).</li><li>Baker, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+of+Biologically+Important+Guanidine-Containing+Molecules+Using+Triflyl-Diurethane+Protected+Guanidines.">Synthesis of Biologically Important Guanidine-Containing Molecules Using Triflyl-Diurethane Protected Guanidines.</a> Synthesis. S1, 1423-1426 (1999).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Digital Lab Techniques: Using a Balance. , (2007).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Digital Lab Techniques: Reaction Work-Up I: Extraction, Washing, and Drying. , (2007).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Digital Lab Techniques: Filtration. , (2007).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Digital Lab Techniques: Reaction Work-Up II: Using the Rotovap. , (2007).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Digital Lab Techniques: Column Chromatography. , (2007).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Flash Chromatography 101. , (2015).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Digital Lab Techniques Manual: TLC - The Basics. , (2007).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Digital Lab Techniques: TLC - Advanced. , (2007).</li><li>Massachusetts Institute of Technology Department of Chemistry Instrumentation Facility. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> NMR Tips and Tricks. , (2015).</li><li>Krohn, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthese+des+Bactereostatischen+2.4-Dibrom-homogentisins&#228;ure+-+Amids+und+Verwandter+Verbindungen.">Synthese des Bactereostatischen 2.4-Dibrom-homogentisins&#228;ure - Amids und Verwandter Verbindungen.</a> Tetrahedron Lett. 16 (52), 4667-4668 (1975).</li><li>Wolkowitz, H., Dunn, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Homogentisic+Acid.">Homogentisic Acid.</a> Biochem. Prep. 4, 6-11 (1955).</li><li>Feichtinger, K., Zapf, C., Sings, H. L., Goodman, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diprotected+Triflylguanidines:+A+New+Class+of+Guanidinylation+Reagents.">Diprotected Triflylguanidines: A New Class of Guanidinylation Reagents.</a> J. Org. Chem. 63, 3804-3805 (1998).</li><li>Ariza, X., Urp&#236;, F., Vilarrasa, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+practical+procedure+for+the+preparation+of+carbamates+from+azides.">A practical procedure for the preparation of carbamates from azides.</a> Tetrahedron Lett. 40, 7515-7517 (1999).</li><li>Ariza, X., Urp&#236;, F., Viladomat, C., Vilarrasa, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=One-Pot+Conversion+of+Azides+to+Boc-Protected+Amines+with+Trimethylphosphine+and+Boc-ON.">One-Pot Conversion of Azides to Boc-Protected Amines with Trimethylphosphine and Boc-ON.</a> Tetrahedron Lett. 39, 9101-9102 (1998).</li><li>Snider, B. B., Song, F., Foxman, B. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Total+Syntheses+of+(&#177;)-Anchinopeptolide+D+and+(&#177;)-Cycloanchinopeptolide.">Total Syntheses of (&#177;)-Anchinopeptolide D and (&#177;)-Cycloanchinopeptolide.</a> D. J. Org. Chem. 65 (3), 793-800 (2000).</li><li>Barykina, O., Snider, B. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+of+(+-)-Eusynstyelamide+A.">Synthesis of (+-)-Eusynstyelamide A.</a> Org. Lett. 12 (11), 2664-2667 (2010).</li><li>Yu, M., Pochapsky, S. S., Snider, B. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+of+(&#177;)-Bistellettadine+A.">Synthesis of (&#177;)-Bistellettadine A.</a> Org. Lett. 12 (4), 828-831 (2010).</li><li>Exp&#242;sito, A., Fern&#225;ndez-Su&#225;rez, M., Iglesias, T., Mu&#241;oz, L., Riguera, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Total+Synthesis+and+Absolute+Configuration+of+Minalemine+A,+a+Guanidine+Peptide+from+the+Marine+Tunicate+Didemnum+rodriguesi.">Total Synthesis and Absolute Configuration of Minalemine A, a Guanidine Peptide from the Marine Tunicate Didemnum rodriguesi.</a> J. Org. Chem. 66, 4206-4213 (2001).</li><li>Wuts, P. G. M., Greene, T. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Greene's Protective Groups in Organic Synthesis. , (2007).</li><li>Malmberg, C. E., Chamberland, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Total+synthesis+of+clavatadine+A+analogues+to+produce+a+viable+reversible+inhibitor+for+factor+XIa.">Total synthesis of clavatadine A analogues to produce a viable reversible inhibitor for factor XIa.</a> , (2015).</li><li>Bhonde, V. R., Looper, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Stereocontrolled+Synthesis+of+(+)-Saxitoxin.">A Stereocontrolled Synthesis of (+)-Saxitoxin.</a> J. Am. Chem. Soc. 133, 20172-20174 (2011).</li><li>Lin, H. Y., Snider, B. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+of+Phidianidines+A+and+B.">Synthesis of Phidianidines A and B.</a> J. Org. Chem. 77, 4832-4836 (2012).</li><li>Hickey, S. M., Ashton, T. D., Pfeffer, F. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Facile+Synthesis+of+Guanidine+Functionalised+Building+Blocks.">Facile Synthesis of Guanidine Functionalised Building Blocks.</a> Asian J. Org. Chem. 4 (4), 320-326 (2015).</li><li>Looper, R. E., Haussener, T. J., Mack, J. B. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chlorotrimethylsilane+Activation+of+Acylcyanamides+for+the+Synthesis+of+Mono-N-acylguanidines.">Chlorotrimethylsilane Activation of Acylcyanamides for the Synthesis of Mono-N-acylguanidines.</a> J. Org. Chem. 76, 6967-6971 (2011).</li><li>Shimokawa, J., Ishiwata, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Total+Synthesis+of+(+)-Batzelladine+A+and+(+)-Batzelladine+D,+and+Identification+of+Their+Target+Protein.">Total Synthesis of (+)-Batzelladine A and (+)-Batzelladine D, and Identification of Their Target Protein.</a> Chem. Eur. J. 11, 6878-6888 (2005).</li><li>Katritzky, A. R., Rogovoy, B. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+Developments+in+Guanylating+Agents.">Recent Developments in Guanylating Agents.</a> ARKIVOC. iv, 49-87 (2005).</li><li>Berlinck, R. G. S., Trindade-Silva, A. E., Santos, M. F. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+chemistry+and+biology+of+organic+guanidine+derivatives.">The chemistry and biology of organic guanidine derivatives.</a> Nat. Prod. Rep. 29, 1382-1406 (2012).</li><li>Ebada, S., Proksch, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chemical+and+Pharmacological+Significance+of+Natural+Guanidines+from+Marine+Invertebrates.">Chemical and Pharmacological Significance of Natural Guanidines from Marine Invertebrates.</a> Mini-Rev. Med. Chem. 11 (3), 225-246 (2011).</li></ol>

The authors have nothing to declare.

准备clavatadine初始努力入伍传统的，间接的方法来胍基的适合的胺的前体，在这种情况下是一个终端叠氮化物。中央这一努力是在分子的两半的结合来构造氨基甲酸酯部分。不幸的是，为了实现在一个计划晚期胍基的预期的叠氮化物还原的所有尝试均告失败。25,26这些挫折启发追求化合物7，这可能在从市售材料的单步通过直接胍基来制备。虽然这种方法已在现有全合成中使用?...

此视频的目的是用来说明如何使用一个直接和早期胍基的方法，使一个终端胍结构更实用，快速，效率比在有机合成传统胍基的方法。胍官能基，在氨基酸精氨酸发现，在许多复杂的天然产物和药物的重要结构元件。发现和含天然产物和小分子新胍的设计建立一个更有效的胍基化的方法的需要。常用的迂回的方式设有引入是在合成的后期阶段揭露潜胍前体。与此相反，一个简单的战术安装了一个受保护的胍到伯胺在合成路线的早期。 胍的被动性通常阻止他们从日常使用没有适当的保护基策略。传统上，方法添加胍官能团参与，参与随后在合成的末尾添加胍多重保护措施的间接方式。最近的两个合成说明固有的间接胍基1,2缺点。本文所报道的直接方法包括被保护的胍试剂与伯胺早在一个给定的分子的合成反应，然后在合成结束时脱保护。这一战略在最近的生物活性生物碱海洋全合成成功部署clavatadine A和phidianidine A和B 3,4。 虽然这种直接胍基方法确实有过胍基的传统方法其优点它还是有它的缺点。的化学条件，该受保护的胍可以生存将取决于所使用的保护基。尽管有这些潜在的缺点，直接胍基方法是一个有利的战略到终端胍添加伯胺为在复杂的有机分子的合成中使用。

<table><tbody><tr><td>Chloroform-d</td><td>Sigma-Aldrich</td><td>612200-100G</td><td>99.8% D, 0.05% v/v tetramethylsilane; Caution: toxic</td></tr><tr><td>Dimethylsulfoxide-d&lt;sub&gt;6&lt;/sub&gt;</td><td></td><td>185965-50G</td><td>99.9% D, 1% v/v tetramethylsilane</td></tr><tr><td>sodium thiosulfate pentahydrate</td><td>Sigma-Aldrich</td><td>S8503-2.5KG</td><td></td></tr><tr><td>sodium sulfate, anhydrous</td><td>Sigma-Aldrich</td><td>238597-2.5KG</td><td></td></tr><tr><td>silica gel</td><td>Fisher Scientific</td><td>S825-25</td><td>Merck, Grade 60, 230-400 mesh</td></tr><tr><td>washed sea sand</td><td>Sigma-Aldrich</td><td>274739-5KG</td><td></td></tr><tr><td>hexane</td><td>Sigma-Aldrich</td><td>178918-20L</td><td>Caution: flammable</td></tr><tr><td>ethyl acetate</td><td>Sigma-Aldrich</td><td>319902-4L</td><td></td></tr><tr><td>methylene chloride</td><td>Sigma-Aldrich</td><td>D65100-4L</td><td></td></tr><tr><td>sodium chloride</td><td>Sigma-Aldrich</td><td>S9888-10KG</td><td></td></tr><tr><td>sodium bicarbonate</td><td>Sigma-Aldrich</td><td>S6014-2.5KG</td><td></td></tr><tr><td>acetic acid</td><td>Sigma-Aldrich</td><td>695092-2.5L</td><td></td></tr><tr><td>hydrochloric acid</td><td>Sigma-Aldrich</td><td>258248-2.5L</td><td>Caution: Corrosive</td></tr><tr><td>bromine</td><td>Sigma-Aldrich</td><td>470864-50G</td><td>&gt;99.99% trace metals basis; Caution: Corrosive, causes severe burns</td></tr><tr><td>hydrobromic acid</td><td>Sigma-Aldrich</td><td>244260-500ML</td><td>48% aqueous; Caution: Corrosive</td></tr><tr><td>2,5-dimethoxyphenylacetic acid</td><td>ChemImpex</td><td>26909</td><td></td></tr><tr><td>chloroform</td><td>Sigma-Aldrich</td><td>132950-4L</td><td>Caution: Toxic</td></tr><tr><td>tetrahydrofuran</td><td>Sigma-Aldrich</td><td>360589-4x4L</td><td>Caution: highly flammable</td></tr><tr><td>&lt;em&gt;N,N&lt;/em&gt;-diisopropylethylamine</td><td>Sigma-Aldrich</td><td>D125806-500ML</td><td>Caution: Corrosive</td></tr><tr><td>triethylamine</td><td>Sigma-Aldrich</td><td>T0886-1L</td><td>Caution: Corrosive</td></tr><tr><td>3 Angstrom molecular sieves</td><td>Sigma-Aldrich</td><td>208574-1KG</td><td></td></tr><tr><td>calcium hydride</td><td>Sigma-Aldrich</td><td>213268-100G</td><td>Caution: Corrosive, reacts violently with water</td></tr><tr><td>ammonium molybdate</td><td>Sigma-Aldrich</td><td>431346-50G</td><td></td></tr><tr><td>phosphomolybdic acid</td><td>Sigma-Aldrich</td><td>221856-100G</td><td></td></tr><tr><td>cerium(IV) sulfate</td><td>Sigma-Aldrich</td><td>359009-25G</td><td></td></tr><tr><td>1-butanol</td><td>Sigma-Aldrich</td><td>537993-1L</td><td></td></tr><tr><td>1,4-butanediamine</td><td>Sigma-Aldrich</td><td>D13208-100G</td><td>Caution: Corrosive / warm in hot water bath to melt prior to use</td></tr><tr><td>triphosgene</td><td>VWR</td><td>200015-064</td><td>Caution: Highly Toxic</td></tr><tr><td>methanol</td><td>Sigma-Aldrich</td><td>646377-4X4L</td><td></td></tr><tr><td>sodium acetate</td><td>Sigma-Aldrich</td><td>241245-100G</td><td></td></tr><tr><td>Dimethylsulfoxide-d&lt;sub&gt;6&lt;/sub&gt;</td><td>Sigma-Aldrich</td><td>570672-50G</td><td>Anhydrous, 99.9% D</td></tr><tr><td>sodium hydroxide</td><td>Sigma-Aldrich</td><td>221465-500G</td><td>Caution: Corrosive</td></tr><tr><td>guanidine hydrochloride</td><td>Sigma-Aldrich</td><td>G4505-25G</td><td>Caution: Toxic, Corrosive</td></tr><tr><td>di-tert-butyl dicarbonate</td><td>VWR</td><td>200002-018%</td><td>Caution: Toxic / may warm in hot water bath to melt prior to use</td></tr><tr><td>trifluoromethanesulfonic anhydride</td><td>Fisher Scientific</td><td>50-206-771</td><td>98%, anhydrous; Caution: toxic, corrosive, extremely moisture sensitive</td></tr></tbody></table>

a direct, early stage guanidinylation protocol for the synthesis of complex aminoguanidine-containing natural products

胍官能团的氨基酸精氨酸，生命的基本构建模块之一最显着位置，是许多复杂的天然产物和药物发现的重要结构元素。由于新的含胍天然产品和设计的小分子，不断发现快速，高效的胍基化方法是浓厚的兴趣，合成和药物有机化学的。由于胍的亲核性和碱性会影响后续的化学变化，传统的，间接的胍基通常追求。间接方法通常采用涉及潜胺的前体多重保护步骤，例如叠氮化物，邻苯二甲酰亚胺，或氨基甲酸酯。通过绕过这些迂回的方法和早期采用直接胍基反应在合成序列中，有可能伪造含clavatadine A的骨干实现线性终端胍这种强效因子XIa抑制剂短小精炼合成。在实践中，盐酸胍阐述与优化生存的合成步骤来精心构造的保护阵列。在clavatadine A的制备，市售二胺直接胍基消除其合成2不必要的步骤。再加上多种已知胍保护基，直接胍基evinces所固有的发现在合成化学家的工具箱中的Home方法简洁，高效的实用性。

市售的α直接胍基，ω二胺，接着用三光气反应，得到作为clavatadine A的线性部分上的反应性异氰酸酯8（ 图1b）。这两步反应序列产率总是较高，95％或更高。胍基试剂6由古德曼描述的方法制备完全相同。11,24 当异氰酸酯8用二溴苯酚3（其合成在图1a</s...

Watch this Scientific Journal Video about A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products at JoVE.com

A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products

Here, we present a protocol for direct, early stage guanidinylation that enables rapid total synthesis of aminoguanidine-containing small organic molecules. An advanced synthetic intermediate used in the synthesis of a blood coagulation factor XIa inhibitor was prepared using this protocol.

一个直接的，早期胍基协议的复杂含氨基胍，天然产物合成

The guanidine functional group, displayed most prominently in the amino acid arginine, one of the fundamental building blocks of life, is an important ...

a-direct-early-stage-guanidinylation-protocol-for-synthesis-complex

Universidad de Cartagena UDEC

Research

JoVE Journal

Chemistry

10.5K 次观看.  Central Washington University. Here, we present a protocol for direct, early stage guanidinylation that enables rapid total synthesis of aminoguanidine-containing small organic molecules. An advanced synthetic intermediate used in the synthesis of a blood coagulation factor XIa inhibitor was prepared using this protocol. 

视频: A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products

Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development

The involvement of free radicals in life sciences has constantly increased with time and has been connected to several physiological and pathological processes. This subject embraces diverse scientific areas, spanning from physical, biological and bioorganic chemistry to biology and medicine, with applications to the amelioration of quality of life, health and aging. Multidisciplinary skills are required for the full investigation of the many facets of radical processes in the biological environment and chemical knowledge plays a crucial role in unveiling basic processes and mechanisms. We developed a chemical biology approach able to connect free radical chemical reactivity with biological processes, providing information on the mechanistic pathways and products. The core of this approach is the design of biomimetic models to study biomolecule behavior (lipids, nucleic acids and proteins) in aqueous systems, obtaining insights of the reaction pathways as well as building up molecular libraries of the free radical reaction products. This context can be successfully used for biomarker discovery and examples are provided with two classes of compounds: mono-trans isomers of cholesteryl esters, which are synthesized and used as references for detection in human plasma, and purine 5',8-cyclo-2'-deoxyribonucleosides, prepared and used as reference in the protocol for detection of such lesions in DNA samples, after ionizing radiations or obtained from different health conditions.

Radical-based biomimetic chemistry has been applied to building-up libraries necessary for biomarker development.

自由基化学生物学的化学行为，生物标记开发

The involvement of free radicals in life sciences has constantly increased with time and has been connected to several physiological and pathological ...

科研

化学

Preparation and In Vivo Use of an Activity-based Probe for N-acylethanolamine Acid Amidase

Activity-based protein profiling (ABPP) is a method for the identification of an enzyme of interest in a complex proteome through the use of a chemical probe that targets the enzyme&#39;s active sites. A reporter tag introduced into the probe allows for the detection of the labeled enzyme by in-gel fluorescence scanning, protein blot, fluorescence microscopy, or liquid chromatography-mass spectrometry. Here, we describe the preparation and use of the compound ARN14686, a click chemistry activity-based probe (CC-ABP) that selectively recognizes the enzyme N-acylethanolamine acid amidase (NAAA). NAAA is a cysteine hydrolase that promotes inflammation by deactivating endogenous peroxisome proliferator-activated receptor (PPAR)-alpha agonists such as palmitoylethanolamide (PEA) and oleoylethanolamide (OEA). NAAA is synthesized as an inactive full-length proenzyme, which is activated by autoproteolysis in the acidic pH of the lysosome. Localization studies have shown that NAAA is predominantly expressed in macrophages and other monocyte-derived cells, as well as in B-lymphocytes. We provide examples of how ARN14686 can be used to detect and quantify active NAAA ex vivo in rodent tissues by protein blot and fluorescence microscopy.

Preparation and In Vivo Use of an Activity-based Probe for N-acylethanolamine Acid Amidase

Here, we describe the preparation and use of an activity-based probe (ARN14686, undec-10-ynyl-N-[(3S)-2-oxoazetidin-3-yl]carbamate) that allows for the detection and quantification of the active form of the proinflammatory enzyme N-acylethanolamine acid amidase (NAAA), both in vitro and ex vivo.

制备及<em&gt;在体内</em&gt;使用基于活动的探针对<em&gt;ñ</em&gt; -acylethanolamine酸酰胺酶

Activity-based protein profiling (ABPP) is a method for the identification of an enzyme of interest in a complex proteome through the use of a chemical ...

生物化学

An Efficient Method for the Synthesis of Peptoids with Mixed Lysine-type/Arginine-type Monomers and Evaluation of Their Anti-leishmanial Activity

This protocol describes the manual solid-phase synthesis of linear peptoids that contain two differently functionalized cationic monomers. In this procedure amino functionalized 'lysine' and guanido functionalized 'arginine' peptoid monomers can be included within the same peptoid sequence. This procedure uses on-resin (N-(1-(4,4-dimethyl-2,6-dioxocyclohexylidene)ethyl) or Dde protection, orthogonal conditions to the Boc protection of lysine monomers. Subsequent deprotection allows an efficient on-resin guanidinylation reaction to form the arginine residues. The procedure is compatible with the commonly used submonomer method of peptoid synthesis, allowing simple peptoids to be made using common laboratory equipment and commercially available reagents. The representative synthesis, purification and characterization of two mixed peptoids is described. The evaluation of these compounds as potential anti-infectives in screening assays against Leishmania mexicana is also described. The protozoan parasite L. mexicana is a causative agent of cutaneous leishmaniasis, a neglected tropical disease that affects up to 12 million people worldwide.

A protocol to synthesize peptoids with mixed cationic functionality in the same sequence is presented (lysine- and arginine-type monomers). Subsequent testing of these compounds against Leishmania mexicana, the protozoan parasites that cause cutaneous leishmaniasis, is also described.

对于拟肽与他们抗利什曼原虫活性混合赖氨酸型/精氨酸型单体及评价合成的有效方法

This protocol describes the manual solid-phase synthesis of linear peptoids that contain two differently functionalized cationic monomers. In this ...

Modification and Functionalization of the Guanidine Group by Tailor-made Precursors

The guanidine group is one of the most important pharmacophoric groups in medicinal chemistry. The only amino acid carrying a guanidine group is arginine. In this article, an easy method for the modification of the guanidine group in peptidic ligands is provided, with an example of RGD-binding integrin ligands. It was recently demonstrated that the distinct modification of the guanidine group in these ligands allows for the selective modulation of the subtype (e.g., between the subtypes &#945;v and &#945;5). Moreover, a formerly unknown strategy for the functionalization via the guanidine group was demonstrated, and the synthetic approach is reviewed in this document. The modifications described here involve terminally (N&#969;) alkylated and acetylated guanidine groups. For the synthesis, tailor-made precursor molecules are synthesized, which are then subjected to a reaction with an orthogonally deprotected amine to transfer the pre-modified guanidine group. For the synthesis of alkylated guanidines, precursors based on N,N&#8242;-Di-Boc-1H-pyrazole-1-carboxamidine are used to synthesize acylated compounds, the precursor of choice being a correspondingly acylated derivative of N-Boc-S-methylisothiourea, which can be obtained in one- and two-step reactions.

A protocol for the synthesis of alkyl-modified guanidines based on the use of the corresponding precursors is presented.

修改和胍集团的官能通过量身定制的前兆

The guanidine group is one of the most important pharmacophoric groups in medicinal chemistry. The only amino acid carrying a guanidine group is arginine. ...

Split-and-pool Synthesis and Characterization of Peptide Tertiary Amide Library

Peptidomimetics are great sources of protein ligands. The oligomeric nature of these compounds enables us to access large synthetic libraries on solid phase by using combinatorial chemistry. One of the most well studied classes of peptidomimetics is peptoids. Peptoids are easy to synthesize and have been shown to be proteolysis-resistant and cell-permeable. Over the past decade, many useful protein ligands have been identified through screening of peptoid libraries. However, most of the ligands identified from peptoid libraries do not display high affinity, with rare exceptions. This may be due, in part, to the lack of chiral centers and conformational constraints in peptoid molecules. Recently, we described a new synthetic route to access peptide tertiary amides (PTAs). PTAs are a superfamily of peptidomimetics that include but are not limited to peptides, peptoids and N-methylated peptides. With side chains on both &#945;-carbon and main chain nitrogen atoms, the conformation of these molecules are greatly constrained by sterical hindrance and allylic 1,3 strain. (Figure 1) Our study suggests that these PTA molecules are highly structured in solution and can be used to identify protein ligands. We believe that these molecules can be a future source of high-affinity protein ligands. Here we describe the synthetic method combining the power of both split-and-pool and sub-monomer strategies to synthesize a sample one-bead one-compound (OBOC) library of PTAs.

Peptide tertiary amides (PTAs) are a superfamily of peptidomimetics that include but are not limited to peptides, peptoids and N-methylated peptides. Here we describe a synthetic method which combines&#160;both split-and-pool and sub-monomer strategies to synthesize a one-bead one-compound library of PTAs.

分裂和池合成及肽叔酰胺图书馆表征

Peptidomimetics are great sources of protein ligands. The oligomeric nature of these compounds enables us to access large synthetic libraries on solid ...

Hydrolysis of a Ni-Schiff-Base Complex Using Conditions Suitable for Retention of Acid-labile Protecting Groups

Unnatural amino acids, amino acids containing side-chain functionalities not commonly seen in nature, are increasingly found in synthetic peptide sequences. Synthesis of some unnatural amino acids often includes the use of a precursor consisting of a Schiff-base stabilized by a nickel cation. Unnatural side-chains can be installed on an amino acid backbone found in this Schiff-base complex. The resulting unnatural amino acid can then be isolated from this complex using hydrolysis of the Schiff-base, typically by employing reflux in strongly acidic solution. These highly acidic conditions may remove acid-labile side-chain protecting groups necessary for the unnatural amino acids to be used in microwave-assisted solid-phase peptide synthesis. In this work, we present an efficient hydrolysis and subsequent Fmoc protection of an amino acid isolated from a Ni-Schiff base complex. Hydrolysis conditions presented in this work are suitable for retention of acid-labile side-chain protecting groups and may be adaptable to a variety of unnatural amino acid substrates.

Here, we present an efficient hydrolysis and subsequent Fmoc protection of an amino acid isolated from a Ni-Schiff-base complex. Hydrolysis conditions presented here are suitable for use when retention of acid-labile side-chain protecting groups is required. This technique may be adaptable to a variety of unnatural amino acid substrates.

镍 - 席夫碱的水解复杂环境条件适宜酸不稳定保护基团的保留

Unnatural amino acids, amino acids containing side-chain functionalities not commonly seen in nature, are increasingly found in synthetic peptide ...

Facile Protocol for the Synthesis of Self-assembling Polyamine-based Peptide Amphiphiles (PPAs) and Related Biomaterials

Polyamine-based Peptide Amphiphiles (PPAs) are a new class of self-assembling amphiphilic biomaterials-related to the peptide amphiphiles (PAs). Traditional PAs possess charged amino acids as solubilizing groups (lysine, arginine), which are directly connected to a lipid segment or can contain a linker region made of neutral amino acids. Tuning the peptide sequence of PAs can yield diverse morphologies. Similarly, PPAs possess a hydrophobic segment and neutral amino acids, but also contain polyamine molecules as water solubilizing (hydrophilic) groups. As is the case with PAs, PPAs can also self-assemble into diverse morphologies, including small rods, twisted nano-ribbons, and fused nano-sheets, when dissolved in water. However, the presence of both primary and secondary amines on a single polyamine molecule poses a significant challenge when synthesizing PPAs. In this paper, we show a simple protocol, based on literature precedents, to achieve a facile synthesis of PPAs using solid phase peptide synthesis (SPPS). This protocol can be extended to the synthesis of PAs and other similar systems. We also illustrate the steps that are needed for cleavage from the resin, identification, and purification.

Facile Protocol for the Synthesis of Self-assembling Polyamine-based Peptide Amphiphiles PPAs and Related Biomaterials

The synthesis of polyamine-based peptide amphiphiles (PPAs) is a significant challenge due to the presence of multiple amine nitrogens, which requires judicious use of protecting groups to mask these reactive functionalities. In this paper, we describe a facile method for the preparation of these new class of self-assembling molecules.

自组装多胺基多肽 Amphiphiles (PPAs) 及相关生物材料的简易合成协议

Polyamine-based Peptide Amphiphiles (PPAs) are a new class of self-assembling amphiphilic biomaterials-related to the peptide amphiphiles (PAs). ...

The Synthesis of RGD-functionalized Hydrogels as a Tool for Therapeutic Applications

The use of polymers as biomaterials has provided significant advantages in therapeutic applications. In particular, the possibility to modify and functionalize polymer chains with compounds that are able to improve biocompatibility, mechanical properties, or cell viability allows the design of novel materials to meet new challenges in the biomedical field. With the polymer functionalization strategies, click chemistry is a powerful tool to improve cell-compatibility and drug delivery properties of polymeric devices. Similarly, the fundamental need of biomedicine to use sterile tools to avoid potential adverse-side effects, such as toxicity or contamination of the biological environment, gives rise to increasing interest in the microwave-assisted strategy.
The combination of click chemistry and the microwave-assisted method is suitable to produce biocompatible hydrogels with desired functionalities and improved performances in biomedical applications. This work aims to synthesize RGD-functionalized hydrogels. RGD (arginylglycylaspartic acid) is a tripeptide that can mimic cell adhesion proteins and bind to cell-surface receptors, creating a hospitable microenvironment for cells within the 3D polymeric network of the hydrogels. RGD functionalization occurs through Huisgen 1,3-dipolar cycloaddition. Some PAA carboxyl groups are modified with an alkyne moiety, whereas RGD is functionalized with azido acid as the terminal residue of the peptide sequence. Finally, both products are used in a copper catalyzed click reaction to permanently link the peptide to PAA. This modified polymer is used with carbomer, agarose and polyethylene glycol (PEG) to synthesize a hydrogel matrix. The 3D structure is formed due to an esterification reaction involving carboxyl groups from PAA and carbomer and hydroxyl groups from agarose and PEG through microwave-assisted polycondensation. The efficiency of the gelation mechanism ensures a high degree of RGD functionalization. In addition, the procedure to load therapeutic compounds or biological tools within this functionalized network is very simple and reproducible.

We present a protocol for the synthesis of RGD-functionalized hydrogels as devices for cell and drug delivery. The procedure involves copper catalyzed alkyne-azide cycloaddition (CuAAC) between alkyne-modified polyacrylic acid (PAA) and a RGD-azide derivative. The hydrogels are formed using microwave-assisted polycondensation and their physicochemical properties are investigated.

RGD功能化水凝胶作为治疗应用的工具合成

The use of polymers as biomaterials has provided significant advantages in therapeutic applications. In particular, the possibility to modify and ...

生物工程

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine

Nitrogen-containing heterocycle aziridines are synthetically very valuable for the preparation of azacyclic and acyclic molecules. However, it is very difficult and laborious to make aziridines in optically pure forms on a large scale to apply asymmetric synthesis of aza compounds. Fortunately, we successfully achieved both enantiomers (2R)- and (2S)-aziridine-2-carboxylates with the electron-donating &#945;-methylbenzyl group at the ring nitrogen as non-activated aziridines. These starting aziridines have two distinct functional groups-highly reactive three-membered ring and versatile carboxylate. They are applicable in ring-opening or ring-transformation with aziridine and in functional group transformation to others from carboxylate. Both of these enantiomers were utilized in the preparation of biologically important amino acyclic and/or aza-heterocyclic compounds in an asymmetric manner. Specifically, this report describes the first expedient asymmetric synthesis of both enantiomers of 5, 6-dihydrouracil-type marine natural products biemamide B and D as potential TGF-&#946; inhibitors. This synthesis consisted of regio- and the stereoselective ring-opening reaction of aziridine-2-carboxylate and subsequent formation of 4-aminoteterahydropyrimidine-2,4-dione. One more example in this protocol dealt a highly stereoselective Mukaiyama reaction of aziridine-2-carboxylate and silyl enol ether, following intramolecular aziridine ring-opening to provide easy and facile access to (-)-epiallo-isomuscarine.

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine

In this study, we prepare both enantiomers of aziridine-2-carboxylate, which are used in the asymmetric synthesis of alkaloids, including biemamide B and D, and (-)-epiallo-isomuscarine.

对映草非活化氮丙啶的制备及比咪咪唑B、D和 表皮异毒羯碱的合成

Nitrogen-containing heterocycle aziridines are synthetically very valuable for the preparation of azacyclic and acyclic molecules. However, it is very ...

Preparation of 1&deg; Amines: Azide Synthesis

Direct alkylation of ammonia produces polyalkylated amines, along with a quaternary ammonium salt. To exclusively prepare primary amines, the azide synthesis method can be used.
Azide ions act as good nucleophiles and react with unhindered alkyl halides to form alkyl azides. Alkyl azides do not participate in further nucleophilic substitution reactions, thereby eliminating the chances of polyalkylated products. Alkyl azides are reduced by hydride-based reducing agents, like lithium aluminum hydride, or by catalytic hydrogenation to primary amines. The driving force for such reactions is the elimination of nitrogen gas.
Azide synthesis also works with other electrophiles like epoxides to produce amino alcohols through stereoselective ring-opening reactions. Alkyl azides have an explosive nature and must be carefully handled.

Preparation of 1&amp;deg; Amines: Azide Synthesis

1°胺的制备:叠氮化物合成

Direct alkylation of ammonia produces polyalkylated amines, along with a quaternary ammonium salt. To exclusively prepare primary amines, the azide ...

一个直接的，早期胍基协议的复杂含氨基胍，天然产物合成

摘要

探索更多视频

此视频中的章节

自由基化学生物学的化学行为，生物标记开发

制备及

对于拟肽与他们抗利什曼原虫活性混合赖氨酸型/精氨酸型单体及评价合成的有效方法

修改和胍集团的官能通过量身定制的前兆

分裂和池合成及肽叔酰胺图书馆表征

镍 - 席夫碱的水解复杂环境条件适宜酸不稳定保护基团的保留

自组装多胺基多肽 Amphiphiles (PPAs) 及相关生物材料的简易合成协议

RGD功能化水凝胶作为治疗应用的工具合成

对映草非活化氮丙啶的制备及比咪咪唑B、D和表皮异毒羯碱的合成

1°胺的制备:叠氮化物合成

一个直接的，早期胍基协议的复杂含氨基胍，天然产物合成

摘要

探索更多视频

此视频中的章节

自由基化学生物学的化学行为，生物标记开发

制备及

对于拟肽与他们抗利什曼原虫活性混合赖氨酸型/精氨酸型单体及评价合成的有效方法

修改和胍集团的官能通过量身定制的前兆

分裂和池合成及肽叔酰胺图书馆表征

镍 - 席夫碱的水解复杂环境条件适宜酸不稳定保护基团的保留

自组装多胺基多肽 Amphiphiles (PPAs) 及相关生物材料的简易合成协议

RGD功能化水凝胶作为治疗应用的工具合成

对映草非活化氮丙啶的制备及比咪咪唑B、D和 表皮异毒羯碱的合成

1°胺的制备:叠氮化物合成

对映草非活化氮丙啶的制备及比咪咪唑B、D和表皮异毒羯碱的合成