Acids. -This newly found method gives the title compounds (IV) under mild conditions and in good yields. -(VASIL'EVA, S. A.; KALIMULLINA, L. K.; SAFAROV, M. G.; Chem. Heterocycl. Compd. (N. Y.) 39 (2003) 2, 174-178; Bashkir State Univ., Ufa 450074, Russia; Eng.) -C. Oppel