N-(4-Isocyano-phen-yl)succinamic acid.

In the crystal structure of the title compound, C(11)H(10)N(2)O(3), inversion-related mol-ecules are connected by pairs of O-H⋯O hydrogen bonds. With the exception of the atoms in the carb-oxy-lic acid group, the non-H atoms are roughly coplanar with a maximum deviation from the mean plane of 0.270 (1) Å for the C atom to which the carb-oxy-lic group is attached.

Acylation is rate-limiting in glycosylasparaginase-catalyzed hydrolysis of N4-(4'-substituted phenyl)-L-asparagines.

Glycosylasparaginase catalyzes the hydrolysis of the N-glycosylic bond between N-acetyl-D-glucosamine and L-asparagine in the catabolism of glycoproteins. The mechanism has been proposed to resemble that of serine proteases involving an acylation step where a nucleophilic attack by a catalytic Thr residue on the carbonyl carbon of the N-glycosylic bond gives rise to a covalent beta-aspartyl-enzyme intermediate, and a deacylation step to give the final products. The question posed in this study was: Is the acylation step the rate-limiting step in the hydrolysis reaction as in serine proteases? To answer this question a series of mostly new substituted anilides was synthesized and characterized, and their hydrolysis reactions catalyzed by glycosylasparaginase from human amniotic fluid were studied.