2001 May - 8 articles
The results presented in this paper confirm that the stereochemical outcome of the reversible additions of lithium (R)-methyl p-tolyl sulfoxide to N-arylidene-p-anisidines (NPMP imines) depends on: (a) the reaction conditions used and (b) the electro...
Berberine azide, berberine thiocyanate, and 8-cyano-8H-berberine were prepared from berberine chloride, a quaternary protoberberine alkaloid. The molecular and crystal structures of all compounds are reported and discussed.
A facile and efficient synthetic procedure for effecting the pinacol rearrangement catalyzed by AlCl3 in the absence of solvent is developed. The rearrangement product is obtained at room temperature in a few minutes and in almost quantitative yield....
Neuropeptide Y (NPY), a 36-mer neuromodulator, binds to the receptors Y1, Y2, Y4 and Y5 with nanomolar affinity. They all belong to the rhodopsin-like G-protein coupled, seven transmembrane helix spanning receptors. In this study, Ala-substituted and...
The epoxidation of the natural product α-euphol followed by cleavage of the obtained epoxide with BF3-etherate, provides 3β-hydroxy-eupholanost-8-en-24-one in satisfactory overall yield.
o-Quinodimethane can be generated from =α,α'-dihalo-o-xylenes using zinc in aqueous solution. In the presence of activated dienophiles cycloadducts can be obtained directly. Catalysis with tris-triphenylphosphine ruthenium(II) dichloride reduces side...
The synthesis of 2,4,6-tris(4-N-isopropylamidinophenyl)pyrimidine from 1,3-di(4-bromophenyl)propen-3-one and 4-bromobenzamidine is reported.
A series of neat 4-(2-alkenyl) substituted 5-methyl-3-phenyl-4H-1,2,4-triazoles were thermolyzed at 320 oC producing a rearrangement products, of which the regioisomeric 1- and 2-substituted triazoles were the main products. The group migrations were...
