Synthesis of copolymers from 3,5-dioxo-4,10-dioxatricyclo-[5.2.02,6]dec-8-ene and vinyl monomers by photopolymerization and their biological activities

Photocopolymerizations of 3,5-dioxo-4,10-dioxatricyclo[5.2.0^2,6]dec-8-ene (DDTD) with methacrylic acid (MA) acrylamide (AAm) and vinyl pyrrolidone (VP) were carried out in 2-butanone using dimethoxy benzoin (DMB) as an initiator at 25°C. The structures of the polymers obtained from photopolymerizations of corresponding monomer pairs were confirmed to be poly(DDTD-co-MA), poly(DDTD-co-AAm) and poly(DDTD-co-VP) by ¹H NMR and ¹³C NMR spectroscopies, and the average molecular weights were determined by gel permeation chromatography (GPC). The weight average molecular weights (M_w) of the polymers were in the range 9500–17300. The polymers were soluble in water, dimethyl sulphoxide (DMSO) and dimethyl formamide (DMF). The contents of DDTD units in the copolymers were 19, 37 and 45%. The in vitro cytotoxicities of the polymers were evaluated using mouse mammary carcinoma (FM-3A), mouse leukaemia (P-388) and human histiocytic lymphoma (U-937) cell lines. The in vivo antitumour activities of the polymers were estimated by the survival time of sarcoma 180 tumour-bearing mice. The in vivo antitumour activities of the polymers were greater than those of 5-fluorouracil (5-FU) and monomeric DDTD at a dose of 0·8mgkg^-1. Poly(DDTD-co-AAm) and poly(DDTD-co-VP) showed higher antitumour activity than 5-FU and monomeric DDTD at all doses tested. © 1998 SCI.