Homotyrosine-Containing Cyanopeptolins 880 and 960 and Anabaenopeptins 908 and 915 from <i>Planktothrix agardhii</i> CYA 126/8
作者:Hilary S. Okumura、Benjamin Philmus、Cyril Portmann、Thomas K. Hemscheidt
DOI:10.1021/np800557m
日期:2009.1.23
Two homotyrosine-bearing cyanopeptolins are described from Planktothrix agardhii CYA 126/8. The compounds feature a common homotyrosine-containing cyclohexadepsipeptide and differ by sulfation of an exocyclically located 2-O-methyl-D-glyceric acid residue. In addition we describe two anabaenopeptins, which contain two homotyrosine residues, one of which is N-methylated. The anabaenopeptins have a common cyclopentapeptide portion and differ in the amino acid linked to it via an ureido bond, arginine and tyrosine, respectively.
The synthesis and SAR of calcitonin gene-related peptide (CGRP) receptor antagonists derived from tyrosine surrogates. Part 1
作者:Xiaojun Han、Rita L. Civiello、Charles M. Conway、Deborah A. Cook、Carl D. Davis、Robert Macci、Sokhom S. Pin、Shelly X. Ren、Richard Schartman、Laura J. Signor、George Thalody、Kimberly A. Widmann、Cen Xu、Prasad V. Chaturvedula、John E. Macor、Gene M. Dubowchik
DOI:10.1016/j.bmcl.2012.05.074
日期:2012.7
We have systematically studied the effects of varying the central unnatural amino acid moiety on CGRP receptor antagonist potency and CYP inhibition in a series of ureidoamides. In this Letter, we report the discovery of compound 23, a potent CGRP receptor antagonist with only weak CYP3A4 inhibition. Unlike the triptans, compound 23 did not cause active constriction of ex vivo human cerebral arteries. At doses of 0.3-1 mg/kg (sc), 23 showed robust inhibition of CGRP-induced increases in marmoset facial blood flow, a validated migraine model. Ureidoamide 23 derives from a novel amino acid, 1H-indazol-5-yl substituted alanine as a tyrosine surrogate. (C) 2012 Elsevier Ltd. All rights reserved.
Fully Stereocontrolled Total Syntheses of (−)-Cylindricine C and (−)-2-Epicylindricine C: A Departure in Sulfonamide Chemistry