Abstract
A novel straightforward chemoenzymatic procedure for the synthesis of hyacinthacine stereoisomers based on the aldol addition of dihydroxyacetone phosphate (DHAP) to N-Cbz-prolinal under catalysis by L-rhamnulose 1-phosphate aldolase from E. coli is presented. The synthesis is complemented by a simple and effective purification protocol consisting of ion-exchange chromatography on CM-sepharose. As examples, (-)-hyacinthacine A2 [the enantiomer of (+)-hyacinthacine A2], 7-deoxy-2-epialexine (the enantiomer of 3-epihyacinthacine A2), ent-7-deoxyalexine (the enantiomer of 7-deoxyalexine) and 2-epihyacinthacine A2 were synthesized by these procedures and characterized for the first time. These new isomers were assayed as inhibitors of glycosidases. As a result, (-)-hyacinthacine A2 demonstrated to be a good inhibitor of α-D-glucosidase from rice whereas the natural enantiomer, hyacinthacine A2, was not. Moreover, a new family of inhibitors of α-L-rhamnosidase was uncovered. © 2007 Wiley-VCH Verlag GmbH & Co. KGaA.
Original language | English |
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Pages (from-to) | 1661-1666 |
Journal | Advanced Synthesis and Catalysis |
Volume | 349 |
Issue number | 10 |
DOIs | |
Publication status | Published - 1 Jul 2007 |
Keywords
- Aldol reaction
- Aldolases
- Amino aldehydes
- Hyacinthacines
- Polyhydroxylated pyrrolizidine alkaloids