PROCEDE DE PREPARATION DES DERIVES DE 6-DEOXYTETRACICLYNE

• Main Author: FAUBL,HERMANN,US
• Format: Patent
• Language: French; Romanian
• Published: 12.04.1982
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAININGELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN,SULFUR, SELENIUM OR TELLURIUM; APPARATUS THEREFOR; BLASTING; CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; FUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS ANDORDNANCE, e.g. CANNONS; GENERAL METHODS OF ORGANIC CHEMISTRY; HEATING; HUMAN NECESSITIES; HYGIENE; LIGHTING; MECHANICAL ENGINEERING; MEDICAL OR VETERINARY SCIENCE; METALLURGY; MOUNTINGS FOR SMALLARMS OR ORDNANCE; ORGANIC CHEMISTRY; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; PREPARATIONS FOR MEDICAL, DENTAL, OR TOILET PURPOSES; THEIR RELEVANT APPARATUS; TRANSPORTING; WEAPONS

Hydrogenation of the exocyclic methylene gp. of a 6-deoxy-6-demethyl-6-methylene-tetracycline (I), or its acid addition salt, in a stereoselective manner giving the alpha-isomer in preference to the beta-isomer, is carried out at 20-100 degrees C and 1-100 atmos. under neutral conditions, or using a weakly acidic acid addn. salt, in the presence of a catalytic amt. of a cpd. of formula Rh(OCOR)2(P C6H5 3) (II) (where R = H, 1-6C alkyl, ClCH2, Cl2CH, Cl3C, FCH2, F2CH, F3C, phenyl, chlorphenyl, tolyl, anisyl). The ratio of alpha-isomer to beta-isomer is >=9:1. Known methods give a less favourable ratio e.g. 1:1.