Abstract: A method for producing an optically active piperidine carboxylic acid derivative, which comprises subjecting a piperidine carboxylic acid derivative of the formula (1): wherein Z is a protecting group for the carboxyl group, to optical resolution by means of an optical resolution agent of the formula (2): wherein symbol * indicates that the designated carbon atom is asymmetric.

Abstract: A method for producing an optically active piperidine carboxylic acid derivative, which comprises subjecting a piperidine carboxylic acid derivative of the formula (1): 1

Abstract: Disclosed are cardiotonic medicines containing, as the active ingredient, at least one of compounds of formula (I) and their pharmacologically acceptable salts when they form salts. ##STR1## wherein X.sup.1 and X.sup.2 do not exist or represents an oxygen atom; A represents OH or a C.sub.1 -C.sub.4 acyloxy group; B represents a hydrogen atom or may form a chemical bond along with A; X is an oxygen atom, nitrogen, sulfur, etc.; R.sup.1 and R.sup.2 each represents a hydrogen atom, a C.sub.1 -C.sub.4 alkyl group, etc.; R.sup.3 and R.sup.4 each represents a hydrogen atom, a C.sub.1 -C.sub.4 alkyl group, etc., or they may together form a 1,4-butylene or 1,5-pentylene group. The compounds have a strong activity of reinforcing the contraction of cardiac muscles and a strong activity of reducing the rate of heart beats. As they are not toxic, they are useful as cardiotonic medicines.

Abstract: An agent for enhancing the drug effects of an antitumor drug, which comprises a compound of the formula I: ##STR1## or a pharmaceutically acceptable salt of the compound.

Abstract: A process for the optical resolution of a pyranobenzoxadiazole compound represented by the formula [(.+-.)I]: ##STR1## which comprises reacting the compound [(.+-.)I] with an optically active carboxylic acid represented by the formula [II]: ##STR2## and separating the diastereomeric salt thus formed is disclosed.

Abstract: Compounds of the formula (I): ##STR1## in which the nitrogen-containing hetero ring portion is 1,4-dihydropyridine ring or a pyridine ring, R.sup.1 is only present when the nitrogen-containing hetero ring is a 1,4-dihydropyridine ring, and Z is a group of the formula (II): ##STR2## in which R.sup.4 and R.sup.5 may be the same or different and together may form one divalent group, are effective agents for enhancing the antitumor effect of antitumor drugs.

Abstract: A compound of the formula (I): ##STR1## wherein X.sup.1 and X.sup.2 do not exist or represent oxygen atom; A represents OH or acyloxy group having 1 to 4 carbon atoms; B represents hydrogen atom; A and B together represent a bond; R.sup.1 and R.sup.2 represent hydrogen atom or alkyl group having 1 to 4 carbon atoms, or R.sup.1 and R.sup.2 together represent 1,2-ethylene, 1,3-propylene, 1,4-butylene or 1,5-pentylene, and these alkylene groups may be substituted by alkyl group having 1 to 4 carbon atoms; R.sup.3 represents amido group of the formula: ##STR2## wherein n, R.sup.4, R.sup.5, R.sup.6, R.sup.7. R.sup.8. R.sup.9, R.sup.10 and R.sup.11 represent specific groups, and the pharmacological acceptable salts of the compounds which can form salts have strong activity for lowering blood pressure, and process therefor and pharmaceutical use of the compounds.

Abstract: A hydrazine derivative having the formula: ##STR1## wherein R is a hydrogen atom or ##STR2##

Abstract: Compounds of the formula (I): ##STR1## in which the nitrogen-containing hetero ring portion is a 1,4-dihydropyridine ring or a pyridine ring, R.sup.1 is only present when the nitrogen-containing hetero ring is a 1,4-dihydropyridine ring, and Z is either a CO.sub.2 R.sup.8 group or a group of the formula (II): ##STR2## in which R.sup.4 and R.sup.5 may be the same or different and together may form one divalent group, are effective agents for enhancing the antitumor effect or antitumor drugs.

Abstract: A process for the optical resolution of a pyranobenzoxadiazole compound represented by the formula [(.+-.)I]: ##STR1## which comprises reacting the compound [(.+-.)I] with an optically active carboxylic acid represented by the formula [II]: ##STR2## and separating the diastereomeric salt thus formed is disclosed.

Abstract: A compounds of the formula (I): ##STR1## wherein A represents OH or OC(O)CH.sub.3-n X.sub.n, B represents hydrogen atom, or A and B together represent a bond; R.sup.1 represents hydrogen atom, R.sup.2 represents hydrogen atom, C(Z)CH.sub.3-n X.sub.n or C(Z)NHCH.sub.3-n X.sub.n or R.sup.1 and R.sup.2 together represents (CH.sub.2).sub.m, (CH.sub.2).sub.m-1 C(Z), N(R.sup.3)(CH.sub.2).sub.2 C(Z), (CH.sub.2).sub.m-2 NHC(Z) or (CH.sub.2).sub.m-2 OC(Z) in which X represents fluorine atom, chlorine atom, bromine atom, a methyl group or a methoxy group and n represents 0 or an integer of 1 to 3, Z represents oxygem atom or sulfur atom, m represents an integer of 4 or 5 and R.sup.3 represents hydrogen atom or a methyl group, and pharmacological acceptable salts of the compounds which can form salts, processes therefor and pharmaceutical use of the compounds.

Abstract: A compound of the formula: ##STR1## wherein each of R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 which may be the same or different, is hydrogen or C.sub.1 -C.sub.4 alkyl; one of X.sup.1 and X.sup.2 is nitro, fluroine, chlorine, difluoromethyoxy or trifluoromethyl and the other is hydrogen, or both of X.sup.1 and X.sup.2 are chlorine; and Y is ##STR2## wherein A is C.sub. -C.sub.6 alkylene, each of Ar.sup.1 and Ar.sup.2 which may be the same or different, is phenyl which may be substituted by chlorine, fluorine or C.sub.1 -C.sub.3 alkoxy, and m is an integer of from 0 to 4, or Y is ##STR3## wherein A, Ar.sup.1 and Ar.sup.2 are as defined above when that both X.sup.1 and X.sup.2 are chlorine; or a pharmaceutically acceptable salt thereof.

Abstract: A process for producing an .alpha.-(benzylidene)acetonylphosphonate of the formula: ##STR1## wherein Ar is phenyl substituted by at least one substituent selected from the group consisting of fluorine, chlorine, bromine, nitro, chloromethyl, dichloromethyl, trichloromethyl, trifluoromethyl, --CO.sub.2 R.sup.7 wherein R.sup.7 is C.sub.1 -C.sub.5 alkyl, --CONR.sup.7 R.sup.8 wherein R.sup.7 is as defined above and R.sup.8 is C.sub.1 -C.sub.5 alkyl, --C(O)R.sup.7 wherein R.sup.7 is as defined above, --OC(O)R.sup.7 wherein R.sup.7 is as defined above, --OSO.sub.3 R.sup.7 wherein R.sup.7 is as defined above, --OCF.sub.3, --S(.dbd.O).sub.2 R.sup.7 wherein R.sup.7 is as defined above, --CN and --SO.sub.3 R.sup.7 wherein R.sup.7 is as defined above, and each of R.sup.1 and R.sup.2 which may be the same or different is a saturated or unsaturated C.sub.1 -C.sub.12 aliphatic group, or R.sup.1 and R.sup.

Abstract: An optical isomer of a compound having the formula: ##STR1## wherein the two methyl groups at 4- and 6-positions of the dioxaphosphorinane ring assume trans configurations to each other, which has a levo-rotatory angle of optical rotation attributable to the asymmetric carbon atom at 4-position of the dihydropyridine ring, and a pharmaceutically acceptable salt thereof.

Abstract: A compound of the formula: ##STR1## wherein X is hydrogen or fluorine and n is 2 or 3; or its pharmaceutically acceptable salt.

Abstract: A compound of the formula: ##STR1## where X is hydrogen, nitro, trifluoromethyl, fluorine, chlorine, bromine or iodine; A is 1,3-propylene or 1,4-butylene which may be substituted by C.sub.1 -C.sub.3 alkyl, R is C.sub.1 -C.sub.4 alkyl, --Y--N(R.sup.1)(R.sup.2) or ##STR2## where each of R.sup.1, R.sup.2 and R.sup.3, which may be the same or different are hydrogen, C.sub.1 -C.sub.6 alkyl, or aralkyl, and Y is C.sub.2 -C.sub.6 alkylene, and Me is methyl, or its pharmaceutically acceptable salt. These compounds have utility as anti-hypertensive agents and coronary or peripheral vasodilators.