A new approach toward the total synthesis of (+)-batzellaside B

Abstract

SummaryA new synthetic approach to (+)-batzellaside B from naturally abundant L-pyroglutamic acid is presented in this article. The key synthetic step involves Sharpless asymmetric dihydroxylation of an olefinic substrate functionalized with an acetoxy group to introduce two chiral centres diastereoselectively into the structure. Heterocyclic hemiaminal 4, which could be converted from the resulting product, was found to provide stereospecific access to enantiomerically enriched allylated intermediate, offering better prospects for the total synthesis of this natural product.

Glycal mediated synthesis of piperidine alkaloids: fagomine, 4-epi-fagomine, 2-deoxynojirimycin, and an advanced intermediate, iminoglycal

“…1) acts as a potent glycosidase inhibitor. 6 The batzellasides 6 are a novel class of C-alkylated iminosugars originally isolated from Batzella sp., a marine sponge from Madagascar 7 a and are active against Staphylococcus epidermidis . Their unique structural features resemble an intriguing extension of the iminosugar frameworks, hence their synthesis 7 b , c has attracted the attention of researchers who practice contemporary drug discovery.…”

Stereoselective Total Synthesis of (–)‐Batzellasides A, B, and C

“…The first total synthesis of natural (+)‐ D ‐batzellaside B was reported by Yoda's group in 2011,3a and the absolute configuration of natural (+)‐ D ‐batzellaside B was determined to be 1 S ,3 S ,4 S ,5 R ,8 S . However, the synthesis required 22 steps starting from a known tribenzyl ether derived from L ‐arabinose, and only resulted in a 3.9 % overall yield, although a new formal synthetic route has been reported 3b. Herein, we report on the efficient and stereoselective total synthesis of (–)‐ L ‐batzellasides A, B, and C, which are the enantiomers of these natural products, starting from commercially available tri‐ O ‐benzyl‐ D ‐glucal ( 1 ) 4…”

Evolution of the Total Syntheses of Batzellasides the First Marine Piperidine Iminosugar

“…and Raispalia sp., collected in Western Australia, together with the detection by LC-MS of 1,4-dideoxy-1,4-imino-D-xylitol and isomeric polyhydroxylated pyrrolidines [35]. As a part of our research program on the synthesis of biologically active iminosugars [36][37][38][39][40][41][42][43], we have been engaged in the total synthesis of (+)-batzellaside B (1b) as a representative member of piperidine iminosugars [44,45]. The main purpose of our firstgeneration synthesis of batzellaside B was to determine the complete structure of this natural product.…”