... 1 Page 6. ... an 8SY0 yield of l-cyclohexyl-3-(2-fluoroethyl)ureu (3c), which i5 consonant with the usual behavior of nitros~ureas.~~~' 9) JL Iloi ... Kitrosation of 3a in undiluted formic acid with an equal volume of aqueous nitrite solution (5- 6%) gave a mixture of isomers (about 657G ...