Abstract: There is disclosed novel eburnamonine oxime, its derivatives and salts, process for the manufacture thereof and pharmaceutical agents containing the same. The compounds are represented by the following formula. ##STR1## wherein R is hydrogen, alkyl, alkoxyalkyl, or oxisilanylalkyl group or a group of ##STR2## R.sup.1 and R.sup.2 are same or different and respectively hydrogen, alkyl having 1 to 4 carbon atoms, aryl or aralkyl group, or R.sup.1 represents together with R.sup.2 and the neighboring nitrogen atom a non-substituted or substituted heterocyclic ring, and n is an integer of 2 or 3.

Abstract: A 2,5-benzodiazocine derivative represented by a formula ##STR1## wherein R.sub.1 is phenyl or p-methoxyphenyl, R.sub.2 is hydrogen or methyl, and R.sub.3 is p-methoxyphenethyl, 3-(p-fluorobenzoyl)-propyl, cyclopropylmethyl or ##STR2## or a salt of such novel compound as well as a CNS-active pharmaceutical agent containing as an effective component at least one of said derivatives and salts.

Abstract: A process for the preparation of carboxylic acids represented by a formula ##STR1## wherein R.sub.1 represents hydrogen atom or a lower alkyl radical, R.sub.2 represents hydrogen atom, lower alkyl or allyl radical and R.sub.3 represents phenyl, substituted phenyl, substituted naphthyl, dibenzofuranyl or substituted biphenyl. Following novel enamine and amidine compounds as intermediates for manufacturing the carboxylic acids and processes for the manufacture of said enamine and amidine compounds ##STR2## wherein R.sub.1, R.sub.2 and R.sub.3 represent the meanings as referred to and R.sub.4 represents dimethylamino, pyrrolidyl, piperidyl or morpholyl.