Verfahren zur Herstellung eines Derivates des 3,5-Dioxo-pyrazolidins.

摘要

The invention comprises 3 : 5-dioxopyrazolidines of the general formula (or tautomeric forms thereof), wherein R represents a hydrocarbon radical containing an O or S linkage, which linkage is separated from the pyrazolidine nucleus by an aliphatic chain of at least one and at most four carbon atoms, and their salts, and the manufacture thereof by processes analogous to those described in Specification 707,611. The chain length of the radical R is preferably not more than 10 members, including the hetero atom and counting a phenyl radical as 4 chain members. The products possess analgesic, antipyretic and antiphlogistic properties. In examples: (1) b -methylmercaptoethylmalonic ester and hydrazobenzene are heated in a solution of sodium ethoxide in ethanol to produce 1 : 2-diphenyl-3 : 5-dioxo-4-(b -methylmercaptoethyl)-pyrazolidine; (2) b -methoxyethylmalonic ester similarly yields 1 : 2-diphenyl-3 : 5-dioxo-4-(b -methoxyethyl)-pyrazolidine; (3) 1 : 2-diphenyl-3 : 5-dioxopyrazolidine is heated with ethoxyacetaldehyde in alcohol in the presence of Raney nickel and under 20 atmospheres pressure of hydrogen to form 1 : 2-diphenyl-3 : 5-dioxo-4-ethoxyethylpyrazolidine. Tables give the properties of additional products in which R is b -n- or -iso-propyl-, -phenyl-, -p-tolyl-, -o : p-dimethylphenyl-, -p-chlorophenyl- or -ethylmercaptoethyl, g - phenylmercaptopropyl, d - phenylmercaptobutyl or b -n-propoxy-, -n-butoxy- or -phenoxy-ethyl. Reference has been directed by the Comptroller to Specification 646,597.ALSO:Aqueous solutions of water-soluble salts (especially those with alkali metals or with organic bases such as ethylene - diamine, diethylamine or triethanolamine) of 1 : 2-diphenyl- 3 : 5-dioxopyrazolidines of the general formula (wherein R represents a hydrocarbon radical containing an O or S linkage, which linkage is separated from the pyrazolidine nucleus by an aliphatic chain of at least one and at most four carbon atoms) may be used as solubility promoters for medicaments difficulty soluble in water, e.g. 1-phenyl-2 : 3-dimethyl-4-dimethylaminopyrazolone. Reference has been directed by the Comptroller to Specification 646,597, [Group IV (b)].