Studios on Azine Compounds. IV

Cv. the Azine and Azonium Compounds of the Proteolytic Enzymes

THE immense importance of the establishment of the chemical nature of the proteolytic enzymes has led to many endeavours to purify them. From the earliest attempts of Schwann [1836] to the present day all these have met with obvious failure. In 1905 it was observed by T. Brailsford Robertson [1907] that if one drop of saturated safranine (Griibler) is added to a solution of trypsin (Griibler) a...

The reaction of azine compounds with proteolytic enzymes.

4-(Diethyl­amino)­salicyl­aldehyde azine

The title compound, C(22)H(30)N(4)O(2), has a crystallographic inversion center located at the mid-point of the N-N single bond. Apart from the four ethyl C atoms, the non-H atoms are nearly coplanar with a mean deviation of 0.0596 (2) Å. An intra-molecular O-H⋯N hydrogen bond occurs. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into layers parallel to (100).

Sn(IV) Compounds Interaction with Metal-Schiff Base Complexes

The formation constants and Gibbs free energy for the interaction of RnSnClm (n = m = 2, R = Me, Ph, n-Bu or n = 4, m = 0, R = Ph) compounds as acceptors, with ML complexes (H2L = N,N'-bis(salicylidene)-2-aminobenzylamine (salabza-H2) and its derivatives, M = Mn2+ or Zn2+), as donors in N,N'-dimethylformamide (DMF) as solvent were studied. These parameters were measured by using UV-vis spectrop...

2,4-Dimethoxy­benzaldehyde azine

The title mol-ecule, C(18)H(20)N(2)O(4), is located on a crystallographic centre of symmetry. The meth-oxy groups are coplanar with the benzene ring [interplanar angles of 14.4 (2) and 3.1 (3)°], indicating a conjugation effect.