Abstract: Crystalline sulfuric, di-nitric, mono-hydrochloric, di-hydrochloric, and di- and sesqui-orthosphosphoric acid addition salts of 7-[.alpha.-(2-aminothiazol-4-yl)-.alpha.-(Z)-methoxyiminoacetamido]-3-[(1- methyl-1-pyrrolidinio)methyl]-3-cephem-4-carboxylate are stable even at elevated temperatures. The crystalline sulfuric acid addition salt is made by forming an admixture of (a) at least one molar equivalent of sulfuric acid with (b) zwitterion in an amount so as to be present in the admixture at a concentration of greater than 25 milligrams/ml, causing crystallization, separating the crystals, washing and drying. The crystalline monohydrochloride, dihydrochloride, and orthophosphate salts are prepared by dissolving the zwitterion in the appropriate amount of acid, causing crystallization by adding acetone and isolating the crystals. Physical admixtures of the salts with certain bases in proportions to give a pH ranging from about 3.

Abstract: Crystalline sulfuric, di-nitric, mono-hydrochloric, di-hydrochloric, and di- and sesqui-orthosphosphoric acid addition salts of 7-[.alpha.-(2-aminothiazol-4-yl)-.alpha.-(Z)-methoxyiminoacetamido]-3-[(1- methyl-1-pyrrolidinio)methyl]-3-cephem-4-carboxylate are stable even at elevated temperatures. The crystalline sulfuric acid addition salt is made by forming an admixture of (a) at least one molar equivalent of sulfuric acid with (b) zwitterion in an amount so as to be present in the admixture at a concentration of greater than 25 milligrams/ml, causing crystallization, separating the crystals, washing and drying. The crystalline monohydrochloride, dihydrochloride, and orthophosphate salts are prepared by dissolving the zwitterion in the appropriate amount of acid, causing crystallization by adding acetone and isolating the crystals. Physical admixtures of the salts with certain bases in proportions to give a pH ranging from about 3.

Abstract: Crystalline sulfuric, di-nitric, mono-hydrochloric, di-hydrochloric, and di- and sesqui-orthosphosphoric acid addition salts of 7-[.alpha.-(2-aminothiazol-4-yl)-.alpha.-(Z)-methoxyiminoacetamido]-3-[(1- methyl-1-pyrrolidinio)methyl]-3-cephem-4-carboxylate are stable even at elevated temperatures. The crystalline sulfuric acid addition salt is made by forming an admixture of (a) at least one molar equivalent of sulfuric acid with (b) zwitterion in an amount so as to be present in the admixture at a concentration of greater than 25 milligrams/ml, causing crystallization, separating the crystals, washing and drying. The crystalline monohydrochloride, dihydrochloride, and orthophosphate salts are prepared by dissolving the zwitterion in the appropriate amount of acid, causing crystallization by adding acetone and isolating the crystals. Physical admixtures of the salts with certain bases in proportions to give a pH ranging from about 3.

Abstract: Processes for the preparation of stable, crystalline cephalosporin intermediates of the formula ##STR1## wherein X is HI or HCl, and Nu and Nu.sup..sym. are certain N-containing heterocyclic rings attached via a sulfur atom or a ring nitrogen atom, respectively, which are substantially free of the .DELTA..sup.2 isomer; processes for intermediates in the preparation of the above compounds; and processes for the preparation of broad-spectrum cephalosporin antibiotics.

Abstract: Stable, crystalline cephalosporin intermediates of the formula ##STR1## wherein X is HI or HCl and Nu and Nu.sup..sym. are certain N-containing heterocyclic rings attached via a sulfur atom or a ring nitrogen atom, respectively, which are substantially free of the .DELTA..sup.2 isomer; processes for, and intermediates in, the preparation of the above compounds; and processes for the preparation of broad-spectrum cephalosporin antibiotics.

Abstract: Optionally substituted silicon isocyanates are prepared by reacting a corresponding silicon halide with an alkali metal cyanate or an alkaline earth metal cyanate in an inert solvent having a dielectric constant below about 10, in the presence of a crown ether as a catalyst.