145013-07-6Relevant academic research and scientific papers
The Total Synthesis of the Bioactive Natural Product Plantazolicin A and Its Biosynthetic Precursor Plantazolicin B
Fenner, Sabine,Wilson, Zoe E.,Ley, Steven V.
supporting information, p. 15902 - 15912 (2016/10/24)
Herein, we describe our full investigations into the synthesis of the peptide-derived natural product plantazolicin A, a compound that demonstrates promising selective activity against the causative agent of anthrax toxicity, and its biosynthetic precurso
COMPOUNDS AND COMPOSITIONS AS CHANNEL ACTlVATING PROTEASE INHIBITORS
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Page/Page column 29, (2008/12/08)
The invention provides compounds and pharmaceutical compositions thereof, which are useful for modulating channel activating proteases, and methods for, using such compounds to treat, ameliorate or prevent a condition associated with a channel activating protease, including but not limited to prostasin, PRSS22, TMPRSS11 (e.g., TMPRSS11B, TMPRSS11E), TMPRSS2, TMPRSS3, TMPRSS4 (MTSP-2), matriptase (MTSP-1), CAP2, CAP3, trypsin, cathepsin A, or neutrophil elastase.
Flexible and convergent total synthesis of cyclotheonamide B
Bastiaans, Harold M.M.,Van der Baan, Juul L.,Ottenheijm, Harry C.J.
, p. 3880 - 3889 (2007/10/03)
A convergent approach using two key intermediates, segment A [a L-proline-L-α-hydroxy-β-homoarginine-D-phenylalamine (Pro-hArg-D-Phe) tripeptide] and segment B [a vinylogous L-tyrosine-L-2,3-diaminopropanoic acid (vTyr-Dpr) dipeptide], was developed for the synthesis of cyclotheonamide B. The starting compound for the preparation of the hArg moiety 7, the predominant part of segment A, was N(α)-(benzyloxycarbonyl)-N(ω),N(ω)'-bis(tert-butyloxycarbonyl)-l-ar ginine methyl ester (15), which was converted into the aldehyde 16 and subsequently homologated using [tris(methylthio)methyl]lithium as a carboxylic acid anion equivalent. Coupling with properly protected Pro and D-Phe derivatives gave smoothly the desired Pro-hArg-D-Phe tripeptide derivative 24. The key feature of segment B, i.e., the L-tyrosine-derived α,β-unsaturated γ-amino acid 4, was prepared by a Wadsworth-Emmons olefination of the aldehyde 29 derived from N-(tert-butyloxycarbonyl), O-tert-butyl-L-tyrosine methyl ester (28). Selective N-(tert-butyloxycarbonyl) removal in the presence of the aryl tert-butyl ether present in the fully protected segment B, i.e., 32, was achieved by treatment with trimethylsilyl triflate/2,6-lutidine to give vTyr-Dpr dipeptide derivative 34 in quantitative yield. Coupling of the key intermediates 24 and 34 using 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium tetrafluoroborate (TBTU) afforded the protected linear pentapeptide 35 in high yield. Treatment of 35 with Pd(PPh3)4/morpholine resulted in simultaneous removal of the C-terminal allyl group and the N-terminal allyloxycarbonyl group to yield 36. Ring closure was effected under dilution conditions by treatment with TBTU/1-hydroxybenzotriazole/4-(dimethylamino)pyridine and gave the protected cyclopentapeptide 37 in 61% yield. Oxidation of the hydroxyl group with Dess-Martin periodinane (24 h, 40°C) in the presence of tert-butyl alcohol gave 38, which was then subjected to O,N-deprotection with trifluoroacetic acid/thioanisole. Subsequent HPLC purification afforded cyclotheonamide B in an overall yield of 1.8% in 17 steps.
Total synthesis of cyclotheonamide B, a facile route towards analogues
Bastiaans, Harold M. M.,Van Der Baan, Juul L.,Ottenheijm, Harry C. J.
, p. 5963 - 5966 (2007/10/02)
A flexible, convergent synthesis of cyclotheonamide B (1b) was developed, starting from the constituent amino acids, using conventional benzyl-, t-butyl- and allyl-based protecting groups. By modification of the key intermediates, this approach allows the preparation of cyclotheonamide analogues.
A Mild and Efficient Method for the Preparation of Guanidines
Poss, Michael A.,Iwanowicz, Edwin,Reid, Joyce A.,Lin, James,Gu, Zhengxiang
, p. 5933 - 5936 (2007/10/02)
A mild and efficient method for the preparation of guanidines by reaction of an acylated thiourea with an amine followed by removal of the acyl groups(s) from the intermediate acylguanidine is reported.Key Words: acylguanidine, acylthiourea, guanidine, water soluble carbodiimide
