- A concise synthesis of a very late antigen-4 antagonist trans-4-[1-[[2,5-dichloro-4-(1-methyl-3-indolylcarboxyamide)phenyl]acetyl]-(4S) -methoxy-(2S)-pyrrolidinylmethoxy]cyclohexanecarboxylic acid via reductive etherification
-
This contribution describes a concise synthesis to ethyl trans-[(4S)-methoxy-(25)-pyrrolidinylmethoxy] cyclohexanecarboxylate (2b) as a key intermediate of very late antigen-4 (VLA-4) antagonist trans-4-[1-[[2,5- dichloro-4-(1-methyl-3-indolylcarboxyamide)phenyl]acetyl]-(4S)-methoxy-(2S) -pyrrolidinylmethoxy] cyclohexanecarboxylic acid (1). The synthesis employs a reductive etherification as a key reaction using (2S,4S)-1-benzyloxycarbonyl-4- methoxypyrrolidine-2-carboxyaldehyde (12) and trans-4- triethylsilyloxycyclohexanecarboxilic acid ethyl ester (13b). This synthesis provides 2b in 6 steps with 38% overall yield from commercially available starting material.
- Chiba, Jun,Muro, Fumihito,Setoguchi, Masaki,Machinaga, Nobuo
-
experimental part
p. 882 - 886
(2012/09/08)
-
- Aromatic amidine derivatives useful as selective thrombin inhibitors
-
The present invention relates to a novel thrombin inhibitor which is effective even when orally administered. More specifically, the present invention relates to an aromatic amidine derivative represented by formula (I) and the salts thereof, which show potent selective inhibitory activity for thrombin in which (a), R, R1, R2, R3, A, W, Y and n are defined as described in the specification.
- -
-
-