| 摘要 |
PURPOSE: To readily obtain a benzothiazine derivative which is useful as a therapeutic agent for circulatory system disease and glaucoma through reduced procedure steps by using a tertiary phosphine and a dialkyl azodicarboxylate to effect the reaction of a specific OH-containing benzothiazine analog with an alcohol. CONSTITUTION: In the presence of (A) a tertiary phosphine such as triphenyl phosphine and (B) a compound of the formula: RO2 CN=NCO2 R (R is a lower alkyl), for example, diisopropyl azodicarboxylate, (C) a compound of formula I (R<1> is a lower alkoxy; R<2> is a lower alkyl) is allowed to react with (D) a compound of formula II (R<3> is R<2> ; Q<1> and Q<2> are each an alkylene) to give (E) a compound of formula III, for example, 3,4-dihydro-2- 5-methoxy-2-[3-(N- methyl-N- 2-[3,4-methylenedioxy)phenoxy]ethyl}amino)propoxy]phenyl}-4- methyl-3-oxo-2H-1,4-benzothiazine or its salt. |
