4s-ferrugineone and 4s,5s-ferrugineol as pheromones of palm weevils were synthesized in 3 and 4 steps, respectively, starting from nonane-5-one employing samp-/ramp -hydrazone methodology. 5-nonanone is transformed to its corresponding ramp hydrazone by reaction with the enantiomerically pure hydrazine ramp. metalation with lithium diisopropylamide (lda) in ether to form azaenolate, followed by...

Some new isatin3hydrazone derivatives that are Isatin3(benzylidene)hydrazone, Isatin3-(methyl ethylide)hydrazone, isatin 3-(isoproplylidene)hydrazone have been synthesized from the reaction of isatin3-hydrazone and different aldehydes and ketones. Thestructure of synthesized compound is assigned on the basis of, IR, 1HNMR, 13CNMRdata. The anti microbial activity was done by disk diffusion metho...

We have used the Chemical Structure DataBase (CSDB) of the NCI CADD Group, an aggregated collection of over 150 small-molecule databases totaling 103.5 million structure records, to conduct tautomerism analyses on one of the largest currently existing sets of real (i.e. not computer-generated) compounds. This analysis was carried out using calculable chemical structure identifiers developed by ...

Heterocyclic nucleic acid bases and their analogs can adopt multiple tautomeric forms due to the presence of multiple solvent-exchangeable protons. In DNA, spontaneous formation of minor tautomers has been speculated to contribute to mutagenic mispairings during DNA replication, whereas in RNA, minor tautomeric forms have been proposed to enhance the structural and functional diversity of RNA e...

Two intramolecularly hydrogen-bonded arylhydrazone (aryl = phenyl or naphthyl) molecular switches have been synthesized, and their full and reversible switching between the E and Z configurations have been demonstrated. These chemically controlled configurational rotary switches exist primarily as the E isomer at equilibrium and can be switched to the protonated Z configuration (Z-H(+)) by the ...

4S-ferrugineone and 4S,5S-ferrugineol as pheromones of palm weevils were synthesized in 3 and 4 steps, respectively, starting from nonane-5-one employing SAMP-/RAMP -hydrazone methodology. 5-nonanone is transformed to its corresponding RAMP hydrazone by reaction with the enantiomerically pure hydrazine RAMP. Metalation with lithium diisopropylamide (LDA) in ether to form azaenolate, followed by...

Proton tautomerism is a general phenomenon in organic molecules and plays a vital role in many fields of chemistry and biochemistry. The tautomerism of salicylideneanilines [eq(1)] has attracted a considerable attention because it is closely related to thermoand photochromism. Salicylideneanilines greatly favor the enol form over the cis-keto form in the gas phase. We demonstrate here that the ...