83553-80-4Relevant articles and documents
Chemistry of opium alkaloids, 45. Improvements in the total synthesis of morphine
Meuzelaar, Gerrit J.,Van Vliet, Michiel C. A.,Maat, Leendert,Sheldon, Roger A.
, p. 2315 - 2321 (2007/10/03)
The chiral 1,2,3,4-tetrahydroisoquinoline intermediates in the Price and Beyerman routes to morphine, (+)-(R)-1-(3-hydroxy-4-methoxybenzyl)-6-methoxy- 1,2,3,4-tetrahydroisoquinoline (6) and (+)-(R)-1-(3,5-dibenzyloxy-4- methoxybenzyl)-6-methoxy-1,2,3,4-tetrahydroisoquinoline (5), were prepared in high ee by ruthenium-catalyzed asymmetric transfer hydrogenation of the corresponding imine precursors (Noyori method). The yield of the key raw material in the Beyerman route, 3,5-dibenzyloxy-4-methoxyphenylacetric acid (1), starting from gallic acid methyl ester (7) was improved by a factor of 5 over previously described syntheses. Key steps in the new procedure are the selective formation of methyl 3,5-dihydroxy-4-methoxybenzoate (9) via the 3,5-diacetate and an improved benzylation of the hydroxyl groups in 9.
VOM RADIOAKTIVEN CONIFERIN ZUM MARKIERTEN TURGORIN
Schildknecht, Hermann,Milde, Reiner
, p. 23 - 32 (2007/10/02)
The first Periodic Leaf Movement Factor ("PLMF 1"), 4-O-(β-D-glucopyranosyl 6-sulfate)gallic acid (1), which is chemonastically active on Mimosa pudica L., and its (14)C-carboxyl-labelled analog were synthesized by Koenigs-Knorr reaction of a D-glucose derivative with a suitably blocked gallic acid to give 4-O-β-D-glucopyranosylgallic acid after deblocking.Regioselective sulfatation with sulfur trioxide-pyridine afforded 1.The (14)C-labelled analog was prepared via regioselective glucosylation of methyl galloate with 2,3,4,6-tetra-D-acetyl-α-D-glucopyranosyl bromide and subsequent sulfatation of the deblocked glucoside.