NOUVEAUX 3-PHENYL-4-OXO-4H-BENZOPYRANNE-CARBOXALDEHYDES, LEUR PREPARATION ET LEUR APPLICATION A L'ALIMENTATION DES ANIMAUX

摘要

1495305 5,7-Dihydroxy-3-phenyl-4-oxo-4H- benzopyran carboxaldehydes PFIZER Ltd 10 Sept 1976 [12 Sept 1975] 37552/75 Heading C2C [Also in Division A5] Novel compounds of the Formula II wherein R is formyl in the 6- or 8-position and R1 is an optional halogen in the 8- or 6-position respectively ; R3 is hydrogen or alkyl; R4 is halogen, hydroxy, C 2-8 -alkanoyloxy, alkyl, alkoxy, nitro, amino, C 2-8 alkanoylamino, sulphonylamino or (SO 2 NR5R6 wherein R5 and R6 are hydrogen or alkyl or R5 and R6 together with the nitrogen atom form a saturated heterocyclic group and n is 0 to 3, or any two of the moieties R4 represent alkylenedioxy attached to adjacent carbon atoms of the benzene ring, wherein alkyl alkoxy and alkylene groups have 1 to 4 carbon atoms, may be prepared by (1) where R 1 is hydrogen and (R4) n does not contain a free amino or a sulphamoyl group, by heating a compound V with hexamine in glacial acetic acid or by reacting V with hydrogen cyanide, a cyanogen halide or zinc cyanide in the presence of hydrogen chloride or a Lewis acid; (2) where R 1 and R 2 are hydrogen and (R4) n is other than or does not contain hydroxy, acyloxy, amino or sulphamoyl, reacting a compound III wherein (R9) n is as defined for (R4) n immediately above, with at least two molar proportions of dimethyl formamide in the presence of a p-toluene sulphonyl chloride; (3) where R 1 is halogen, by halogenation of compounds II in which R 1 is hydrogen; (iv) where (R4) n is or includes amino, by the reduction of the corresponding nitro substituted compound II; (v) optional acylation of the product of (iv) to form an alkanoylamino or sulphonylamino group; (vi) where (R4) n is or includes sulphamoyl, by chlorosulphonation followed by reaction with ammonia or a dialkyl or cyclic amine. 5 - Hydroxy - 3 - (4 - methoxyphenyl) - 7 - noctanoyloxy - 4 - oxo - 4H - benzopyran - 8 - carboxaldehydedihydrate, pharmaceutical compositions of which are claimed, is prepared by esterification of the corresponding 5,7-dihydroxy compound.