Antiatherosclerotic furochromones and intermediates therefor

Abstract

The present invention particularly provides novel furochromones and intermediates for their preparation.

Description

BACKGROUND OF THE INVENTION

The present application relates to novel furochromone compounds which are useful in the treatment of atherosclerosis. The use and preparation of these compounds is described in application Ser. No. 378,686, filed 17 May 1982, which is incorporated herein by reference.

PRIOR ART

Methods of the total synthesis of khellin are known, as are certain chemical intermediates useful in its synthesis.

The use of pyrogallol in the synthesis of khellin intermediates is known. For example, the transformation of pyrogallol to the khellin intermediate 1-(2,3-dihydro-6,7-dihydroxy-5-benzofuranyl)ethanone is known. The parahydroxylation of this intermediate is also known. See Row, L. R., et al., Indian J. Chem., 5:105 (1967) describing this transformation and the subsequent dimethylation to yield known khellin intermediates. U.S. Pat. No. 4,284,569 provides a variety of novel anti-atherosclerotic furochromones.

SUMMARY OF THE INVENTION

The present invention particularly provides:

(a) a benzofuran of formula III wherein R.sub.2 is C.sub.1 -C.sub.4 alkyl;

(b) a benzofuran of formula IV wherein R.sub.5 is C.sub.2 -C.sub.4 alkyl;

(c) a benzofuran of formula V wherein one of R.sub.6 and R.sub.7 is C.sub.1 -C.sub.4 alkyl and the other is C.sub.2 -C.sub.4 alkyl with the proviso that R.sub.6 and R.sub.7 are different; and

(d) an anti-atherosclerotic furochromone of formula VI wherein one of R.sub.6 and R.sub.7 is C.sub.1 -C.sub.4 alkyl and the other is C.sub.2 -C.sub.4 alkyl with the proviso that R.sub.6 and R.sub.7 are different; wherein R.sub.12 is --CH.sub.2 --S(O).sub.n --R.sub.20, wherein n is zero, one or two and R.sub.20 is C.sub.1 -C.sub.5 alkyl;

wherein R.sub.13 is:

(1) hydrogen; or (2) chloro, iodo, or bromo.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention particularly provides 4-Ethoxy-9-methoxy-7-methylthiomethylfurochromone and 4-Methoxy-9-ethoxy-7-methylthiomethylfurochromone.

Claims

1. An anti-atherosclerotic furochromone of formula VI:

wherein one of R.sub.6 and R.sub.7 is C.sub.1 -C.sub.4 alkyl and the other is C.sub.2 -C.sub.4 alkyl with the proviso that R.sub.6 and R.sub.7 are different;

wherein R.sub.12 is --CH.sub.2 --S(O).sub.n --R.sub.20, wherein n is zero, one or two and R.sub.20 is C.sub.1 -C.sub.5 alkyl;

wherein R.sub.13 is:

(1) hydrogen, or

(2) chloro, iodo or bromo.

2. 4-Ethoxy-9-methoxy-7-methylthiomethylfurochromone, a compound according to claim 1.

3. 4-Methoxy-9-ethoxy-7-methylthiomethylfurochromone, a compound according to claim 1.