Total Synthesis of the Anti Methicillin-Resistant Staphylococcus aureus Peptide Antibiotics TAN-1057A-D
摘要:
TAN-1057A-D, dipeptides isolated from bacteria Flexibacter sp. PK-74 and PK-176, are new antibiotics with potent antibacterial activity against methicillin-resistant Staphylococcus aureus. We describe, in detail, the total synthesis of TAN-l057A-D by a convergent route featuring a new method to construct the cyclic amidinourea functional group.
Total Synthesis of the Anti Methicillin-Resistant Staphylococcus aureus Peptide Antibiotics TAN-1057A-D
摘要:
TAN-1057A-D, dipeptides isolated from bacteria Flexibacter sp. PK-74 and PK-176, are new antibiotics with potent antibacterial activity against methicillin-resistant Staphylococcus aureus. We describe, in detail, the total synthesis of TAN-l057A-D by a convergent route featuring a new method to construct the cyclic amidinourea functional group.
23 (30%). The latter was deprotected by hydrogenolysis to give the final compound as a mixture of two epimers − TAN-1057A, B − isolated previously from a strain of Flexibacter sp. PK-74. The intermediate 3 was prepared from 3-amino-2-(N-Z-N-methylamino)propionic acid methyl ester hydrochloride (16) and 2-methyl-2-thiopseudobiuret hydroiodide (18) in one step in 35% yield.
First enantioselective synthesis of the novel antiinfective TAN-1057A via its aminomethyl-substituted dihydropyrimidinone heterocycle
作者:Vladimir N. Belov、Michael Brands、Siegfried Raddatz、Jochen Krüger、Sofia Nikolskaya、Viktor Sokolov、Armin de Meijere
DOI:10.1016/j.tet.2004.06.034
日期:2004.8
Enantiomerically pure N-2-Z-N-2-MeAsnOH [(S)-14], prepared in 8 steps (23% overall yield) from asparaginic acid, was first subjected to a Hofmann degradation with PhI(OCOCF3)(2) yielding (S)-N-2-Z-N-2-methyl-2,3-diaminopropanoic acid [N-2-Z-N-2-Me-L-A(2)pr, (S)-15], and this in turn was protected to give N-2-Z-N-3-Boc-N-2-Me-L-A(2)pr [(S)-17]. Condensation of (S)-17 with HN=C(SMe)NHCONH2 followed by removal of the tert-butoxycarbonyl protecting group, cyclization and hydrogenolytic removal of the Z-group gave the heterocycle of TAN-1057A [(S)-1] with an e.e. of 87 in 36% yield [from (S)-14]. Coupling of (S)-1 with (S)-tris-Z-beta-homoarginine (20a) in the presence of O-(7-azabenzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU) and iPr(2)NEt in N,N-dimethyl-acetamide followed by hydrogenolysis afforded the most active A-diastereomer of the natural antibiotic TAN-1057 in 52% yield (from (S)-1 and 20a). Similarly, starting from (S)-1, a single diastereomer of the potent, less toxic TAN-1057A analogue 22b with a beta-lysine side chain has been prepared. All described synthetic steps do not require column chromatography for purification of the products. (C) 2004 Elsevier Ltd. All rights reserved.
Total Synthesis of the Anti Methicillin-Resistant <i>Staphylococcus aureus</i> Peptide Antibiotics TAN-1057A-D
作者:Chenguang Yuan、Robert M. Williams
DOI:10.1021/ja972670j
日期:1997.12.1
TAN-1057A-D, dipeptides isolated from bacteria Flexibacter sp. PK-74 and PK-176, are new antibiotics with potent antibacterial activity against methicillin-resistant Staphylococcus aureus. We describe, in detail, the total synthesis of TAN-l057A-D by a convergent route featuring a new method to construct the cyclic amidinourea functional group.