As part of our studies on pyrimidine derivatives, 27 4-alkyl-2-(1-piperazinyl)-5, 6-polymethylenepyrimidines and structurally related derivatives were synthesized, and their hypoglycemic activities were examined in mice treated with 2-deoxy-D-glucose. Most of the derivatives showed higher activity at a dose of 30 mg/kg p.o. than tolbutamide at a dose of 100 mg/kg p.o. The structure-activity relationships are discussed.
The Preparation and Properties of Some Cyclic β-Diketone Diimines
作者:Kenneth Charles Moss、Frank Price Robinson
DOI:10.1139/v73-077
日期:1973.2.15
six-membered cyclic β-diketones to form Schiff bases was investigated. Mass spectral data show that reaction occurred on the side-chain carbonyl except where steric hindrance forced condensation to occur on the ring carbonyl. N.m.r. studies show that these Schiff bases exist primarily in the ketamine form in solution, irrespective of the solvent. I.r. data confirm this. The preparation of a number of
ketone, in up to 93 % ee (ee=enantiomeric excess), as well as for the asymmetricFriedel-Craftsamination of a variety of 2-naphthols, permitting the preparation of the latter in up to 98 % ee. The aminated 8-amino-2-naphthol itself is the first chiral organocatalyst based on non-biarylatropisomerism. The two enantiomers of this chiral primary amine can be used for the direct alpha-fluorination of alpha-branched
Flash vacuum thermolysis of β-keto-trimethylsilyl-enol-ethers
作者:J. Jullien、J.M. Pechine、F. Perez、J.J. Piade
DOI:10.1016/0040-4020(82)80222-6
日期:1982.1
Thermolysis at 800° of a series of β-keto-trimethylsilyl-enol-ethers allows the elimination of a trimethylsilanol molecule through a 1,5 rearrangement. The reaction products are furanic derivatives, which are obtained in often good yields through an allenic intermediate, which has been isolated.
condensation gives endocyclic enamines 3 as the thermodynamically favored products. Activation with Lewis acid BF(3).OEt(2) affords betaines 8 as intermediate products, which can be reacted with L-valine diethylamide (2) to preferentially furnish exocyclic enamines 4 as kinetic products. Derivatives with quaternary stereocenters were accessible from both isomeric enamines by using asymmetric, copper(II)-catalyzed