A visual pigment is composed of retinal bound to its apoprotein by a protonated Schiff base linkage. Light isomerizes the chromophore and eventually causes the deprotonation of this Schiff base linkage at the meta II stage of the bleaching cycle. The meta II intermediate of the visual pigment is the active form of the pigment that binds to and activates the G protein transducin, starting the vi...

In this study, mononuclear octahedral cobalt(III) Schiff base complex [CoL3], L = (5-bromo-2-hydroxybenzyl-2-furylmethyl)imine, was synthesized from the reaction of Co(NO3)2•6H2O and the Schiff base ligand L in methanol as solvent. It used as a new precursor to prepare spinel type cobalt oxide nanoparticles by a facile solid-state thermal decomposition. Controlling the temperature and time, Co3...

Two biologically active Schiff bases, C13H10BrON (4), C13H9Br2O2N (5), were synthesized by the reaction of 2-aminophenol (1) with 3-bromobenzaldehyde (2) or 3,5-dibromo-4hydroxybenzaldehyde (3) in the presence of conc. H2SO4. The characterization of Schiff bases were carried out by using spectroscopic techniques including IR, H-NMR, FAB-MS along with elemental analyses. The Schiff bases were ch...

At alkaline pH the bacteriorhodopsin mutant D85N, with aspartic acid-85 replaced by asparagine, is in a yellow form (lambda max approximately 405 nm) with a deprotonated Schiff base. This state resembles the M intermediate of the wild-type photocycle. We used time-resolved methods to show that this yellow form of D85N, which has an initially unprotonated Schiff base and which lacks the proton a...

Schiff base denotes a reaction product of a primary amine and a carbonyl compound. Schiff bases possess a wide variety of biological activity specially antibacterial and antifungal properties. Metal complexes of Schiff base have been studied for their biological activities. This review articles provide a summary of medicinal chemistry features of Schiff base and various reports published on bio...

Addition of Potassium cyanide to a mixture of Schiff base and lithium perchlorate afforded a-aminonitriles in high yields. Addition of potassium cyanide to a methanolic solution of Schiff base and phosphoric acid afforded a-aminonitriles. When the reaction mixture was refluxed it gave a-amino acids in high yields.

Reaction between Schiff-base ligand and half-sandwich complex M(Pc)(acac) led to the isolation of new sandwich-type mixed (phthalocyaninato)(Schiff-base) di-lanthanide compounds M2(Pc)2(L)H2O (M = Dy, Gd) (1, 2) [H2Pc = metal free phthalocyanine, Hacac = acetylacetone, H2L = N,N'-bis(3-methyloxysalicylidene)benzene-1,2-diamine] with the triple-decker molecular structure clearly revealed by sing...

The binding of chloride is known to shift the absorption spectrum of most long-wavelength-absorbing cone-type visual pigments roughly 30 nm to the red. We determined that the chloride binding constant for this color shift in the gecko P521 visual pigment is 0.4 mM at pH 6.0. We found an additional effect of chloride on the P521 pigment: the apparent pKa of the Schiff base in P521 is greatly inc...

A new class of rhodopsins covalently linked to an enzymatic domain was discovered recently. A member of this class of enzymerhodopsins, the rhodopsin-guanylyl cyclase (RhGC) was identified in the aquatic fungus Blastocladiella emersonii (BE). Characterization of RhGC showed that the second-messenger molecule cGMP (cyclic guanylyl monophosphate) is produced upon green light illumination. Here, t...

Attaching dialkylaminomethyl arms to commercial phenolic oxime copper extractants yields reagents which transport base metal salts very efficiently by forming neutral 1:1 or 1:2 complexes with zwitterionic forms of the ligands.