N-(Fluoren-9-ylmethoxy­carbon­yl)-l-isoleucine

In the crystal structure of the title compound [systematic name fluoren-9-ylmethyl N-(1-carb­oxy-2-methyl­butyl)carbamate], C(21)H(23)NO(4), the mol­ecular plane of the O=C—NH—C(α) unit is slightly pyramidalized. The N atom deviates from the basal plane by 0.2086 (12) Å. The O=C—N—C(α) torsion angle is −17.2 (2)°, and the C—N and O=C bond lengths are 1.3675 (17) and 1.2122 (17) Å, respectively. Apparently the character of the sp (2) hybrids of the mol­ecular plane is, to some extent, reduced. The crystal structure exhibits two inter­molecular hydrogen bonds (O—H⋯O and N—H⋯O), in which the hydr­oxy O atom acts as a donor to the carbonyl group and an acceptor of the amide group, respectively.