The aim of this review is to cover recent advances in acylation chemistry (peptide, amide, and ester bond formation) in which ethyl 2-cyano-2-(hydroxyimino)acetate (Oxyma)-derived reagents are involved. The distinct applications of each class of Oxyma derivatives will be discussed and compared to the behavior of reputed standards in the field. Outline

In the title compound, C(20)H(18)N(2)O(2), weak inter-molecular C-H⋯O and C-H⋯N inter-actions generate a chain that runs parallel to the b axis and incorporates C(7) and R(2) (2)(15) graph-set motifs. The supra-molecular aggregation is completed by the presence of weak C-H⋯π inter-actions.

Moderate to excellent entantio- and stereoselectivities (ee’s 54-100%) were observed in PLE catalyzed hydrolysis of (±)-ethyl 5-oxo-endo-tricyclo[5.2.1.02,6] deca-8-ene-2-carboxylate 5 and the structurally related open chain bicyclic structures (±)-ethyl 3-acetylbicyclo[2.2.1]hept-5-ene-2-carboxylates 7, 9 and (±)-ethyl 3-propanoylbicyclo[2.2.1]hept-5-ene-2-carboxylates 8, 10. A pronounced pref...

The mol-ecule of the title compound, C11H13ClN2O2, is approximately planar (r.m.s. deviation = 0.099 Å for non-H atoms) and adopts a Z conformation about the C=N double bond. In the crystal, mol-ecules are linked by N-H⋯O and C-H⋯O hydrogen bonds to the same O-atom acceptor, forming zigzag chains propagating along [010]. These inter-actions give rise to R2(1)(6) loops.

In the title compound, C(11)H(13)BrN(2)O(2), the dihedral angle between the phenyl ring and the almost planar (r.m.s. deviation = 0.011 Å) C-C(Br)=N-N(H)- fragment is 74.94 (16)°. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, which generate C(6) chains propagating in [010]. Weak aromatic π-π stacking [centroid-centroid separation = 3.784 (3) Å] may also help to consolidate the ...

In the title compound, C(13)H(16)N(2)O(4), an intra-molecular N-H⋯O hydrogen bond generates an S(6) ring. The mol-ecule adopts an E configuration with respect to the central C=N double bond. In the crystal, symmetry-related mol-ecules are connected into chains along [010] via weak C-H⋯N hydrogen bonds. The crystal structure is further stabilized by weak C-H⋯π inter-actions.