The synthesis of some N-(P-carbamidinobenzenesylfonyl)-N', N'dialkylguanidine hydrochlorides

An attempt was made to synthesize N-CP-carbamidinobenzenesulfonyl)-N', N'-dialkylguanidlne hydrochlorides wherein their structures resembled those of the common hypoglycemic sulfonylureas. Five N, N-dialkylguanidines were prepared by refluxing two moles of secondary amine with one mole of S-methylisothiourea sulfate in aqueous solution. P-cyanobenzenesulfonyl chloride was made by treating an excess of phosphorus pentachloride with P-sulfamidobenzoic acid with 0.01 part of 96% phosphoric acid being added as a conversion moderator. One mole of N, N-dialkylguanidine sulfate was condensed with two moles of P-cyanobenzenesulfonyl chloride in acetone at a pH of 8-9 controlled through the addition of 50% sodium hydroxide solution, the temperature maintained at 5-10° C. In this way, N-(P-cyanobenzenesulfonyl)-N', N'-dialkylguanidines were obtained in good yield. The corresponding iminoester hydrochlorides, namely, N-(P-carbethoxyiminobenzenesulfonyl)-N', N'-dialkylguanidine hydrochlorides were made by saturating a solution of the corresponding nitrile and absolute ethanol in dry dioxane, with dry hydrogen chloride gas, where the reaction temperature was maintained at 5-10° C. Four iminoester hydrochlorides were converted to the amidine hydrochlorides by treating an alcoholic solution of the respective iminoester hydrochloride with 10% alcoholic ammonia solution at 60° C. Dimethyl, diethyl, pentamethylene and tetramethylene derivatives of iminoester hydrochloride derivatives were prepared. All melting points reported in this thesis were uncorrected and taken on a Fisher Johns melting point apparatus. New amidine hydrochlorides were identified by the data acquired from elemental analysis, infra red spectra, and NMR spectra. A Coleman Model 33 Carbon-Hydrogen and a Coleman Model 29 Nitrogen analyzer were used for the elemental analysis. Infra red and nuclear magnetic resonance spectra were obtained on a Beckmann Model IR 8 and a Varian Model T-60 NMR spectraphotometers.