Abstract: The present invention provides a process for the preparation of 4-hydroxyindole derivatives of the general formula: ##STR1## in which R.sub.1 is a hydrogen atom or an alkyl radical containing up to 6 carbon atoms and R.sub.2 is a hydrogen atom or an alkyl radical containing up to 6 carbon atoms, wherein a compound of the general formula: ##STR2## in which R.sub.2 has the same meaning as above, is reacted with a compound of the general formula:R.sub.3 --CH.sub.2 --CO--COOR.sub.1 (III)in which R.sub.1 has the same meaning as above and R.sub.3 is a reactive residue, to give a 2-(2-imino-6-oxocyclohexylidene)-propionic acid derivative of the general formula: ##STR3## in which R.sub.1, R.sub.2 and R.sub.3 have the same meanings as above, which is then cyclized in known manner to give a compound of the general formula: in which R.sub.1 and R.sub.2 have the same meanings as above, which is subsequently dehydrated.

Abstract: The present invention provides a process for the preparation of 4-hydroxyindole derivatives of the general formula: ##STR1## in which R.sub.1 is a hydrogen atom or an alkyl radical containing up to 6 carbon atoms and R.sub.2 is a hydrogen atom or an alkyl radical containing up to 6 carbon atoms, wherein a compound of the general formula: ##STR2## in which R.sub.2 has the same meaning as above, is reacted with a compound of the general formula:R.sub.3 --CH.sub.2 --CO--COOR.sub.1 (III)in which R.sub.1 has the same meaning as above and R.sub.3 is a reactive residue, to give a 2-(2-imino-6-oxocyclohexylidene)-propionic acid derivative of the general formula: ##STR3## in which R.sub.1, R.sub.2 and R.sub.3 have the same meanings as above, which is then cyclized in known manner to give a compound of the general formula: ##STR4## in which R.sub.1 and R.sub.2 have the same meaning as above, which is subsequently dehydrated.

Abstract: The present invention provides aminopropanol derivatives of the general formula: ##STR1## wherein R.sub.1 is a hydrogen atom or a lower alkanoyl or an aroyl radical, R.sub.2 is a lower alkyl radical or a radical of the general formula: ##STR2## wherein X is a valency bond, a methylene group or an oxygen or sulphur atom, Ar is a monocyclic, carbo- or heterocyclic aryl radical, R.sub.6 and R.sub.7, which can be the same or different, are hydrogen atoms or lower alkyl radicals, R.sub.8 and R.sub.9, which can be the same or different, are hydrogen or halogen atoms, hydroxyl groups, lower alkanoyl radicals, alkenyl radicals, alkynyl radicals, alkyl radicals, lower alkoxy radicals, aralkoxy radicals, alkenyloxy radicals, alkynyloxy radicals, lower alkylthio radicals, aminocarbonyl radicals, aminosulphonyl radicals or acylamino radicals; or R.sub.2 is a 1,4-benzodioxan-2-ylmethyl radical, R'.sub.2 is a hydrogen atom or a benzyl radical, R.sub.

Abstract: The present invention provides indole derivatives of the general formula: ##STR1## wherein R.sub.1 is a hydrogen atom, an aralkyl radical or a radical of the general formula: ##STR2## in which B is a reactive group or, together with R.sub.5, represents a valency bond, and R.sub.5 is a hydrogen atom or an aliphatic or aromatic acyl radical, R.sub.2 is a hydrogen atom or a lower alkyl radical, R.sub.3 is a hydrogen atom, a methyl radical or a --CH.sub.2 --O--R.sub.5 radical, R.sub.5 having the same meaning as above, and R.sub.4 is an aminocarbonyl, cyano, oximinomethyl, formyl, hydroxymethyl or lower alkoxycarbimidoyl radical, with the proviso that R.sub.1 is not an aralkyl radical when R.sub.4 is a formyl radical. The present invention also provides processes for the preparation of these compounds. Furthermore, the present invention is concerned with the use of these compounds for the preparation of compounds with a heart and circulatory activity.