Abstract: A new and improved process for the preparation of ceftriaxon disodium salt hemiheptahydrate of formula I ##STR1## is described, wherein 7-amino-3-{[(2,5-dihydro-6-hydroxy-2-methyl-5-oxo-as-triazin-3-yl)thio]met hyl}-3-cephem-4-carboxylic acid disodium salt is converted with a reactive 2-(2-aminothiazol-4-yl)-2-syn-metoxyimino acetic acid derivative such as 2-benzo-thiazolyl-thio ester in a water solution and in the presence of a suitable inert organic solvent such as acetone, at a temperature between 0.degree. C. and 40.degree. C. and then the desired compound is isolated in a very pure form and with a high total yield.Ceftriaxon is a cephalosporin antibiotic of the third generation for parenteral application and a valuable agent for the treatment of heavy infections.

Abstract: In the process for preparing 4-(2'-nitrophenyl-2,6-dimethyl)-3,5-dicarbmethoxy-1,4-dihydropyridine of the formula ##STR1## 2-nitrobenzaldehyd-diacetate, methyl acetoacetate and ammonia are reacted in the presence of an inert organic solvent, such as methanol, and in the presence or absence of an organic base, such as pyridine, at a temperature of between 20.degree. and 150.degree. C. The compound is a valuable medicine for the treatment of angina pectoris.

Abstract: Preparation of 4-(n-hexadecylamino)-benzoic acid or salt thereof employing as catalyst quaternary ammonium or phosphonium salt.

Abstract: A process of preparing ##STR1## by reacting 4-thiomethyl-5-methyl imidazole with N-cyano-N'-methyl-N"-(2-chloroethyl) guanidine in a two-phase system under the conditions of phase transfer catalysis.