Vitamin=K-1 and K2 E-isomers stereospecific synthesis - by reaction of an alkoxy- or acyloxy-phenyl-carbene-carbonyl metal e.g. chromium complex and oxidation of the reaction product

摘要

In a new process for the stereospecific prodn. of cpds. of the vitamin K1 and K2 series, a phenyl(alkoxy or acyloxy)-carbene-carbonyl-metal complex ix reacted with an enzyme of the formula CH3-C C-R (I) (where R is dimethylallyl, geranyl, farnesyl or an analogous isoprenoid terpenyl or phytyl residue) and the resulting substd. naphthol-carbonyl-metal complex is treated with an oxidising agent which leaves the terpene substit. intact but is capable of splitting the metal-ring bond and converting the ring into the quinonoid form. Process is used in the prodn. of vitamin K1 and K2 cpds. with effects on blood coagulation, suitable for use as feed additives, for metabolic studies, etc. The process favours the formation of the biologically active all-trans (E) form of the prod. over the less active cis (Z) form.