An asymmetric substrate-controlled Morita–Baylis–Hillman reaction as approach for the synthesis of pyrrolizidinones and pyrrolizidines
摘要:
We describe herein an approach to the total synthesis of functionalized pyrrolizidinones and pyrrolizidines. The synthetic sequence is based on a highly stereoselective substrate-controlled Morita-Baylis-Hillman (MBH) reaction between a chiral amino-aldehyde and methyl acrylate. The selectivity attained in this reaction was controlled by the presence of a hydroxyl group adequately placed in the structure of the amino-aldehyde used as the nucleophilic component of the MBH reaction. The MBH adducts were used as substrate for an efficient total synthesis of pyrrolizidinones and pyrrolizidines in good overall yield. (C) 2013 Elsevier Ltd. All rights reserved.
[DE] PROLINDERIVATE ALS PHARMAZEUTISCHE WIRKSTOFFE IN DER TUMORTHERAPIE [EN] PROLINE DERIVATIVES USED AS PHARMACEUTICAL ACTIVE INGREDIENTS FOR THE TREATMENT OF TUMOURS [FR] DERIVES DE PROLINE COMME PRINCIPES ACTIFS PHARMACEUTIQUES DANS LA THERAPIE DES TUMEURS
synthesized from natural amino alcohols or by reduction of formyl esters of α-amino acids and PPh2Cl. Their cationic rhodium complexes have been found to be excellent catalysts for enantioselective hydrogenation of dehydroamino acids (ee ∼ 86%, yield ∼ 100%) for example. Asymmetric reduction of ketones can also be performed with the new alkyl AMPP* modified rhodium catalyst (ee 50%).
A benzamide derivative represented by the formula: ##STR1## having a promoting activity of gastrointestinal tract and pharmacentical composition containing the same.