Fish & Richardson P.C.
Polyheterocyclic compounds
 The present invention relates to a group of polyheterocyclic compounds covered by the following formula: ##STR1## wherein each of X.sub.1, X.sub.2, X.sub.3, and X.sub.4, independently, is O, S, NH, or N(C.sub.1-6 alkyl), but one of them must be O, NH, or N(C.sub.1-6 alkyl); each of R.sub.1, R.sub.2, R.sub.5, and R.sub.6, independently, is H or a substituent (e.g., halogen, CN, NO.sub.2, or C.sub.1-4 haloalkyl), but at least one of them must be a substituent; each of R.sub.3 and R.sub.4, independently, is H, C.sub.1-6 alkyl, CHO, CH.sub.2 OH, or CH.sub.2 NH.sub.2 ; and each of m and n, independently, is 0 or 1. 
Industrial Technology Research Institute
C C
C07D C07D
inventional inventional
Yuh-Lin Ching Te
Yang Chang