SYNTHESIS AND PHYSICOCHEMICAL PROPERTIES OF ALTERNATING COPOLYMERS OFMALEIC-ANHYDRIDE WITH DIHYDROPYRANS CONTAINING 6-CHLOROPURINE, 6-MERCAPTOPURINE, AND HYPOXANTHINE .8.
Mj. Han et al., SYNTHESIS AND PHYSICOCHEMICAL PROPERTIES OF ALTERNATING COPOLYMERS OFMALEIC-ANHYDRIDE WITH DIHYDROPYRANS CONTAINING 6-CHLOROPURINE, 6-MERCAPTOPURINE, AND HYPOXANTHINE .8., Polymer, 37(4), 1996, pp. 667-673
The new monomers, 2-(6-chloro-, 6-hydroxy-, 6-mercapto-, and 6-aminopu
rin-9-ylmethyl)-3,4-dihydro-2H-pyran (3a, 3b, 3c, and 3d, respectively
) and 2-(6-chloro and 6-hydroxypurin-7-ylmethyl)-3,4-dihydro-2H-pyran
(4a and 4b, respectively) were synthesized. Copolymerization of these
monomers with maleic anhydride resulted in the alternating copolymers
5 and 7, which were hydrolysed to give poly[(2-(6-Cl-, OH-, and SH-pur
in-9-ylmethyl)tetrahydropyran-5,6-diyl) (1,2-dicarboxyethylene)])(6a,
6b, and 6c, respectively) and poly[(2-(6-Cl- and OH-purin-7-ylmethyl)
tetrahydropyran-5,6-diyl) (1,2-dicarboxyethylene)] (8a and 8b, respect
ively). The polymers 6 and 8 are polynucleotide analogues, which have
6-chloropurine, hypoxanthine or 6-mercaptopurine as nucleic acid bases
. They showed physico-chemical properties quite similar to those of th
e natural polynucleotides, e.g. polymer 6b showed 23.7% of hypochromic
ity of the u.v. absorption at a wavelength of 250 nm, and 8b exhibited
a broad excimer fluorescence around 422 nm and showed typical polyele
ctrolyte behaviour.