Abstract: 8-Methoxy-quinolonecarboxylic acid derivatives of the formula ##STR1## wherein R.sub.1 is a hydrogen atom, a lower alkyl, a phenylalkyl or an ester residue hydrolyzable in the living body, R.sub.2 is a hydrogen atom or methyl and n is an integer of 1, optical isomers thereof, pharmaceutically acceptable salts thereof and hydrates thereof. The 8-methoxy-quinolonecarboxylic acid derivatives of the present invention have enforced and a wide range of in vitro and in vivo antibacterial effects against Gram-positive bacteria, while retaining a strong antibacterial effect against Gram-negative bacteria, that the conventional quinolonecarboxylic acid antibacterial agents have. In addition, the compounds of the present invention scarcely show problematic side-effects and are low toxic. Therefore, they are expected to show superior clinical effects as antibacterial agents.

Abstract: Novel .beta.-form crystals of 6-(3,6-dihydro-2-oxo-2H-1,3,4-thiadiazin-5-yl)-3,4-dihydro-2(1H)-quinolino ne useful as cardiotonics.

Abstract: An oxodiazine compound of the formula: ##STR1## or a pharamceutically acceptable acid addition salt thereof, wherein each of R.sup.1 and R.sup.2 is hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy, C.sub.1-4 alkoxy-C.sub.1-4 alkoxy, phenyl-C.sub.1-4 alkyl-oxy which may be optionally substituted by at least one substituent selected from the group consisting of halogen, C.sub.1-4 alkyl and C.sub.1-4 alkoxy on the phenyl nucleus, or phenyl which may be substituted by at least one substituent selected from the group consisting of halogen, C.sub.1-4 alkyl and C.sub.1-4 alkoxy on the phenyl nucleus; X is --S--, --CH.dbd.N-- or --C(R.sup.3).dbd.C(R.sup.4)--, where each of R.sup.3 and R.sup.4 is hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy, C.sub.1-4 alkoxy-C.sub.1-4 alkoxy or phenyl-C.sub.1-4 alkyl-oxy which may be optionally substituted by at least one substituent selected from the group consisting of halogen, C.sub.1-4 alkyl and C.sub.

Abstract: A thiadiazine compound of the formula: ##STR1## a method for preparing said compound and a pharmaceutical composition containing said compound, wherein X is methylene which may be optionally substituted by an alkyl of up to 3 carbon atoms; R is hydrogen atom or methyl group; and n is an integer of 1 or 2.Since the compounds exhibit potent cardiotonic and coronary vasodilator activities and further inhibitory activity on platelet aggregation, they are useful as cardiotonic and antithrombotic drugs.

Abstract: 1,4-Dihydropyridine-3,5-dicarboxylic acid ester derivatives of the general formula: ##STR1## or acid addition salts thereof, wherein W is --CH.dbd. or --N.dbd.; Y is --CH.dbd.CH--, --O--, --S--, --CH.dbd.N(O)p-- (p is zero or 1) or --N(R)-- (R is hydrogen or lower alkyl); X.sup.1, X.sup.2 and X.sup.3 are the same or different, and are each hydrogen, halogen, nitro, trifluoromethyl, cyano or lower alkylthio; Z is aryl or 5- or 6-membered aromatic heterocyclic ring (which may have a substituent or two or three substituents which may be the same or different, and the substituent may be halogen, lower alkyl, lower alkoxy, lower alkanoylamino, cyano, nitro, lower alkylthio, trifluoromethyl, sulfamoyl, di-lower alkylsulfamoyl, amino or di-lower alkylamino); ##STR2## is 5- to 7-membered heterocyclic ring which may have nitrogen atom, oxygen atom, sulfur atom or unsaturated bond on the ring, and may be substituted by lower alkyl, lower alkoxycarbonyl, lower alkanoylamino, ethylenedioxy or --(CH.sub.2).sub.m --OR.sup.

Abstract: A dihydropyridine compound of the formula: ##STR1## or a pharmaceutically acceptable acid addition salt thereof, wherein Het is 5- or 6-membered aromatic heteroaryl, R.sup.1 and R.sup.2 are each lower alkyl, R.sup.3 is lower alkyl, R.sup.4 is hydrogen, lower alkyl or aralkyl, R.sup.5 is lower alkyl or aralkyl, and n is 1 or 2. Such compounds are useful as therapeutic agents for myocardial and cerebral ischemic syndroms and hypertension.

Abstract: 1,4-Dihydropyridine-3,5-dicarboxylic acid ester derivatives represented by the formula ##STR1## (wherein Ar.sup.1 and Ar.sup.2 are each the same or different and represent an aryl group; R.sup.1 represents a lower alkyl group; R.sup.2 and R.sup.3 are each the same or different and represent a lower alkyl or aralkyl group; n is 1 or 2; and R.sup.4 represents a lower alkyl) or the acid addition salts thereof. These compounds are useful as antihypertensive agents and as agents for treating the disturbances of cardiac or cerebral circulation.

Abstract: Imidazolido[1,5-c]thiazolidine-3-spiro-4'-piperidine compounds of the formula: ##SPC1##Wherein R.sup.1 represents a member selected from the group consisting of a hydrogen atom, an alkyl group of from 1 to 4 carbon atoms, a benzyl group, a p-chlorobenzyl group, a 4,5-dimethoxybenzyl group, a 4,5,6-trimethoxybenzyl group, a phenethyl group, an acetyl group, a benzoyl group, a trimethoxybenzoyl group, a methoxycarbonyl group, an ethoxycarbonyl group, a 4,4-bis(p-fluorophenyl)butyl group and a group of the formula ##SPC2##(in which Y represents a member selected from the group consisting of H, F and CH.sub.3 O, and n represents an integer of 1, 2 or 3); R.sup.