DE3521456

• Main Authors: SEAGER, JOHN FREDERICK, WARE, HERTFORDSHIRE, GB, DANSEY, ROGER, GREENWAYS, WELWYN, HERTFORDSHIRE, GB
• Format: Patent
• Language: English
• Published: 29.04.1993
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; HETEROCYCLIC COMPOUNDS; METALLURGY; ORGANIC CHEMISTRY; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; THEIR RELEVANT APPARATUS; TRANSPORTING

Compounds of formula (II> in which R1 is C1-4 alkyl, preferably methyl, are prepared by reaction of a compound of formula (I> where Q is hydrogen or a cation derived from a suitable base with a suitable alkylating agent such as an alkyl halide or a dialkyl sulphate. The compound of formula (II) may be converted into a histamine H2-antagonist containing an -NHC(=CHNO2)NHCH3 end group, e.g. ranitidine, by reaction with an appropriate amine. The compound of formula (I) (compounds where Q is H or alkali metal are said to be novel) may be prepared by reaction of methyl isothiocyanate with the carbanion of nitromethane (preferably generated in situ by reaction of nitromethane with a suitable base) in the presence of dimethyl sulphoxide as solvent, Q representing the cation derived from the base used to produce the carbanion of nitromethane.