O6-SUBSTITUTED GUANINE DERIVATIVES, A PROCESS FOR THEIR PREPARATION AND THEIR USE IN TREATING TUMOUR CELLS

摘要

O6-hetarylalkyl- or naphthylalkylguanine derivatives of formula (I) wherein Y is H, ribosyl, deoxyribosyl, or R"XCHR''', wherein X is O or S, R" and R''' are alkyl, or substituted derivatives thereof; R' is H, or alkyl or hydroxyalkyl; R is (i) a cyclic group having at least one 5- or 6-membered heterocyclic ring, optionally with a carbocyclic or heterocyclic ring fused thereto, the or each heterocyclic ring having at least one hereto atom chosen from O, N or S, or a substituted derivative thereof; or (ii) naphthyl or a substituted derivative thereof; and pharmaceutically acceptable salts thereof, exhibit the ability to deplete O6 - alkylguanine-DNA alkyltransferase (ATase) activity. A process for preparation of the compounds is described. The compounds have utility in combination with alkylating agents in the chemotherapeutic treatment of tumour cells.