142870-69-7 6-Cmc-FU 6-O-Carboxymethylchitin-5-fluorouracil Chitin, 6-(2-((6-((5-fluoro-3,4-dihydro-2,4-dioxo-1(2H)-pyrimidinyl)methoxy)-6-oxohexyl)amino)-2-oxoethyl) ether