The hydrazone is then deprotonated on the ?-carbon position by a strong base, such as lithium diisopropylamide ( LDA ), leading to the formation of a resonance stabilized anion-an azaenolate.
22.
The development and modification of Enders'hydrazone alkylation reaction mainly focus on the addition of more steric hindrance on the pyrrolidine rings of both SAMP and RAMP, while preserving the methoxy group for lithium chelation.
23.
A Shapiro reaction of the vinyllithium compound derived from hydrazone "'4.1 "'with aldehyde "'4.2 "'makes the first connection that will become the B ring.
24.
Several reversible reactions have been proposed and / or applied in protein-directed DCC . These included boronate ester formation, diselenides-disulfides exchange, disulphide formation, hemithiolacetal formation, hydrazone formation, imine formation and thiol-enone exchange.
25.
The ?, ?-unsaturated hydrazone is brominated by DDH in allylic position at the sulfonamide nitrogen, which constitutes the capto-dative stabilized radical position, and the bromide ion becomes the leaving group in the following nucleophilic attack of an alcoholate ion.
26.
The first step is the formation of acetone imine, Me 2 C = NH; this is then oxidized by hydrogen peroxide through a complex mechanism to give 3, 3-dimethyloxaziridine, which reacts with a further molecule of ammonia to produce acetone hydrazone.
27.
When the hydrazone "'1 "'in " scheme 5 " is reacted with iodine and triethylamine in toluene, the expected reaction product is not the di-iodide "'10 "'through path B in a free radical mechanism.
28.
"' Methasterone "'( nickname "'Superdrol "'), also known as "'methyldrostanolone "', is an designer steroid . Mebolazine is formed by hydrazone formation between 2 equivalents of methasterone with 1 equivalent of hydrazine.
29.
Recent developments that exploit proximal functional groups have enabled hydrazone condensations to operate at 20 M " 1 s " 1 at neutral pH while oxime condensations have been discovered which proceed at 500-10000 M " 1 s " 1 at neutral pH without added catalysts.
30.
"' Testosterone enanthate benziloylhydrazone "', also known as "'testosterone 17?-enanthate 3-benzilic acid hydrazone "', is a injected anabolic-androgenic steroid and an androgen ester specifically, the C17? enanthate ester and C3 benzilic acid hydrazone of testosterone which was never marketed.
