Influence of additives and storage temperature on physicochemical and microbiological properties of eye drops containing ceftazidime.

The purpose of the studies was to examine the influence of additives and the storage temperature on the physicochemical properties of the eye drops containing ceftazidime and on the antimicrobial activity of ceftazidime in the eye drops stored for 30 days at the temperature of 4 degrees C and 2 degrees C. The eye drops were 1% sterile aqueous solutions of Biotum (Ceftazidimum) in citrate buffer of pH 6.18-6.

Physicochemical and microbiological properties of eye drops containing cefuroxime.

The purpose of the studies was to examine the influence of the additives and storage temperature on physicochemical properties and on the antimicrobial activity of cefuroxime in the eye drops. The eye drops were 1% sterile aqueous solutions of cefuroxime in citrate buffer of pH 6.15-6.

Influence of additives and storage temperature on physicochemical and microbiological properties of eye drops containing cefazolin.

The purpose of the studies was to choose additives for eye drops containing cefazolin and the assessment of the influence of used additives and the storage temperature on the physicochemical properties and the stability of the eye drops. The drops were 1% sterile solutions of cefazolin in citrate buffer of pH 6.15-6.

Synthesis and properties of 4-substituted-1-piperazinyl-propyl derivatives of 1-phenyl-7-methylpyrimido-[4,5-d]pyrimidin-4-one.

In reactions of 1-phenyl-7-methyl-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimido[ 4,5-d]pyrimidin e (1) with 1-(3-chloropropyl)-4-methyl(phenyl, 3-chlorophenyl, 2-pyrimidynyl, 2-thiazolyl)piperazines (5), mixtures of isomeric N- and S-substituted derivatives of compound 1 (3 and 4) were obtained. Isomers were separated by fractional crystallization. The structure of novel compounds 3 and 4 was confirmed by elemental and spectral analyses.

Synthesis and properties of the derivatives of 2-alkylthio-4-oxo-3,4- (and -1,4)-dihydropyrido-[2,3-d]pyrimidine-5- and -6-carboxylic acids.

Condensation of diethyl 2-amino-6-methylpyridine-3,4-dicarboxylate (I) with the corresponding isothiocyanates afforded derivatives of ethyl 4-oxo-2-thioxo-1,2,3,4-tetrahydropyrido [2,3-d]pyrimidine-5-carboxylate (V-VII). Alkylation of (V), (VI) and (XI) gave the corresponding derivatives of ethyl 2-alkylthio-4-oxo-3,4-(and 1,4)-dihydropyrido[2,3-d]pyrimidine-5- and -6- carboxylate [(XII-XVI), (XX-XXII)]. Some of the obtained compounds were active pharmacologically.