Novel optically active isomers or racemates of 1,3-dihydro-3-1-[2-(2,3-dihydro-1,4-benzodioxin-2-yl)-2-hydroxyethyl]-pip eridin-4-yl}-2H-indol-2-ones of the formula ##STR1## wherein R.sub.1 is selected from the group consisting of hydrogen, chlorine, bromine, fluorine and alkoxy of 1 to 5 carbon atoms and R.sub.2 is selected from the group consisting of hydrogen and alkyl of 1 to 5 carbon atoms and their non-toxic, pharmaceutically acceptable acid addition salts having antihypertensive activity and a novel process and intermediates for their preparation.
本发明涉及1,3-二氢-3-1-[2-(2,3-二氢-1,4-苯并二氧杂环-2-基)-2-羟乙基]-
哌啶-4-基}-
2H-吲哚-2-酮的新光学活性异构体或外消旋体,其
化学式为##STR1##其中R.sub.1选自氢、
氯、
溴、
氟和1到5个碳原子的烷氧基的群;R.sub.2选自氢和1到5个碳原子的烷基的群,以及它们的无毒、药学上可接受的酸加盐,具有降压作用,以及其制备的新工艺和中间体。