Yôtaro Kondo

Muraminan (polymuramic acid) and related compounds derived from chitosan

Abstract Chitosan was modified to give N -1-naphthylmethylenechitosan (d.s. 0.92, 1 ), which was tritylated to give N -1-naphthylmethylene)-6- O -tritylchitosan (d.s. 0.97 for trityl, 2 ). Compound 2 was acylated to give a series of 3- O -acyl derivatives (d.s. 0.24–1.0, 4–14 ), and was treated with 2- d , l -chloropropionic acid to give 3- O -(1- d , l -carboxyethyl) derivative (d.s. 0.37, 15 ). Compound 15 was treated in aqueous 1 N HCl to give 3- O -(1- d , l -carboxyethyl) chitosan (d.s. 0.37, 16 , muraminan). Compound 2 was treated with 2- d , l -halopropionic acids in sodium methylsulfinylcarbanion to give 3- O -(1- d , l -carboxyethyl)- N , N -(1- d , l -dicarboxyethyl)- O -tritylchitosan (d.s. 2.9 for carboxyethyl, 17 ). Compound 17 was treated with HCl in methanol to afford 3- O -(1-carboxyethyl)- N , N -(1-dicarboxyethyl) chitosan (d.s. 2.4 for carboxyethyl, 18 ). Compounds 16 and 18 were soluble in water.