GB491351A - Manufacture of benzyl-oxyalkyl and hydroxyalkyl ethers of cinchona alkaloids - Google Patents

Abstract

Cinchona alkaloids containing a phenolic hydroxyl group are converted by treatment with a benzyloxyalkyl aromatic sulphonate into their benzyloxyalkyl ethers, from which the hydroxyalkyl ethers may be obtained by hydrolysis with dilute acid. The benzyloxyalkyl ethers may also be prepared by digesting a chloralkyl ether of the alkaloid with sodium benzylate. The products possess therapeutic properties. The benzyloxyalkyl aromatic sulphonates are prepared by the process described in Specification 491,349. Examples are given of the preparation of (1) benzyloxyethyl apocupreine by alkylation of apocupreine with benzyloxyethyl benzene sulphonate or benzyloxyethyl p-toluene sulphonate; also by alkylation of apocupreine with b -chlorethyl p-toluene sulphonate, followed by digestion of the b -chlorethyl product with sodium benzylate; (2) benzyloxyethyl hydrocupreine by treatment of the potassium salt of hydrocupreine with benzyloxyethyl p-toluene sulphonate; (3) g -benzyloxypropyl apocupreine and a -methyl-b -benzyloxyethyl apocupreine by interaction of potassium apocupreine with g -benzyloxypropyl- and a -methyl-b -benzyloxyethyl p-toluene sulphonates respectively. Further examples describe the hydrolysis of the products of the preceding examples with dilute hydrochloric acid, thereby forming hydroxyethyl apocupreine, hydroxyethyl hydrocupreine, g -hydroxypropyl apocupreine and a -methyl-b -hydroxyethyl apocupreine. British Specification 461,373 and U.S.A. Specification 2,033,514 also are referred to. The sample furnished under Sect. 2 (5) comprises hydroxyethyl hydrocupreidine dihydrochloride, prepared by treating potassium hydrocupreidine with benzyloxyethyl benzene sulphonate and heating the resulting benzyl oxyethyl hydrocupreidine with dilute hydrochloric acid.