Chiral cyclic β-amino acids and their derivatives, pharmaceutical compositions containing them and the use of such compounds

Abstract

The invention relates to chiral cyclic β-amino acids of Formula (I) and their salts formed with pharmaceutically acceptable acids or bases, wherein the main meanings of the substituents are as follows: R stands for CAlk; X stands for —COOH, —CONH, —CONH(CAlk), —CON(CAlk), —COO(CAlk), —COPhe-O—(CAlk) or —CHOH; Y stands for —NH, —NHBoc, —NHFmoc, —NH(CAlk), —N(CAlk), —NHCHPh, or Ar—NH—C(═X)—N(R)— wherein Ar stands for a phenyl group substituted by Calkoxy or halogen, Xstands for O or S, and Rstands for hydrogen or benzyl; and X+Y stands for —CONH— vagy —CON(Boc)-; with the proviso that when X stands for —COOH, then Y may be only different from —NH. The invention also relates to pharmaceutical compositions having multidrug-resistance reversing effect that contain one or more compound(s) of Formula (I) or a salt thereof and inert pharmaceutical carriers and/or auxiliary agents. The invention also relates to carboxylic acids of Formula (XX) and their salts.