FENYLPENTANSYRADERIVAT OCH SETT FOR DERAS FRAMSTELLNING

Phenylpentanoic acid derivs. of formula (I) and their salts are new. In the formula, one of R1 and R2 is H and the other is phenyl carrying 1 or 2 substituents selected from halogen, 1-4C alkyl, 1-4C alkoxy, NO2, amino and 1-4C alkanoylamino; one of R3 and R4 is H and the other is H or 1-4C alkyl; R5 is H and R6 is OH or R5 +R6 is a direct bond; and R7 is H and R8 is OH or R7 + R8 is a direct bond. (I) have ulcer-healing activity. For treating humans and animals, they are administered in a daily oral or subcutaneous dosage of up to 50 (pref. 1-10) mg/kg. Specific cpds. (I) include (+)-6alpha-(p-nitrophenyl)3, 3a alpha, 6, 6a alpha-tetrahydrofuran 3, 4-b furan-2,4-dione. In an example, this is prepd. by nitration of (+)-6alpha-phenyl-3, 3a alpha, 6, 6a alpha-tetrahydrofuro 3, 4-b furan-2,4-dione with KNO3/H2SO4.