NOVEL 7,7-DISUBSTITUTED DERIVATIVES OF (5H,9H)-6,8-DIOXABENZOCYCLOHEPTENE, PREPARATION METHOD THEREOF AND USE OF SAME IN THE SYNTHESIS OF NON-STEROIDAL VITAMIN D ANALOGUES

Optionally 7-substituted or 7,7-disubstituted 2-(formyl or substituted methyl)-(5H,9H)-6,8-dioxabenzocycloheptenes (I) are new. Dioxabenzocycloheptene derivatives of formula (I) and their optical isomers are new. A : -CH 2Y 1> or -CHO; Y 1>halo (specifically Cl or Br), OH, OSO 3R 2> or P(O)(OR 3>) 2; R, R 1>H (but preferably not both H), alkyl, alkoxy or aryl (optionally substituted by 1-5 of halo, alkyl, alkoxy, CN and/or NO 2); or R + R 1>group completing a 5-6C ring (specifically a cyclopentane or cyclohexane ring); R 2>alkyl or aryl; R 3>alkyl. Independent claims are included for: (A) the preparation of (I); (B) the synthesis of non-steroidal vitamin D analogs, specifically (3,4-bis-hydroxymethyl-phenyl)-methyl-substituted biphenyl derivatives of formula (IV), using (I) in at least one of the stages; and (C) the use of biphenyl derivatives of formula (II) for the preparation of (IV). X : CH 2, NH, NR 8> or O; R 4>, R 5>, R 8>1-3C alkyl; R 6>, R 7>Me, Et, CF 3 or C 2F 5; Z 1>OH, NHR 8>, NH 2 or CHO. [Image] [Image] ACTIVITY : None given. MECHANISM OF ACTION : None given.