thiazolidine-4-carboxylic acid [ Heparegen,gamma-thiaproline,norgamem,thiaproline,thiazolidine-4-carboxylic acid, (R)-isomer,thiazolidine-4-carboxylic acid, sodium salt,thioproline ] active against thimerosal intoxication; acts on cell membranes of tumor cells causing reverse transformation to normal cells; RN given refers to parent cpd