Richard W. Draper

An asymmetric synthesis of the novel H3 agonist (+)-(3R,4R)-3-(4-imidazolyl)-4-methylpyrrolidine dihydrochloride (Sch 50971)

Abstract A short, high yielding, enantioselective synthesis of the novel H 3 agonist Sch 50971 1 is described. The key enantiodifferentiating step is the 1,4-addition of a chiral N -propionyloxazolidinone to a nitroolefin.

An Efficient Process for the Synthesis of trans-2,3-Disubstituted-2,3-dihydro-4H-1-benzopyran-4-ones (Chroman-4-ones)

Abstract The piperidine catalyzed Knoevenagel condensation of 2′-aryl/alkyl-2-hydroxyacetophenones 7 and aryl/alkylaldehydes 8 in refluxing isopropyl alcohol with azeotropic removal of water affords, in high yield, equilibrium mixtures of E - and Z -chalcones 9 and cis - and trans -chroman-4-ones 10 which are effectively isomerized in situ to the trans -2,3-diaryl/alkylchroman-4-ones, following the addition of 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU) to the cooled reaction mixture and may be isolated in high purities (91–99%) by simple filtration, with good to excellent yields (70–95%).

Unusual hydroxy-γ-sultone byproducts of steroid 21-methanesulfonylation. An efficient synthesis of mometasone 17-furoate (Sch 32088)

Abstract An efficient two stage synthesis of the steroid anti-inflammatory agent mometasone 17-furoate (Sch 32088) 4 from 17α,21-dihydroxy-16α-methyl-9β,11β-oxidopregna-1,4-diene-3,20-dione 6 is described and the structures of unusual δ-hydroxy-γ-sultone byproducts of 4-dimethylamino-pyridine catalyzed methanesulfonylation of 21-hydroxy-20-ketosteroids are deduced.

Novel steroidal chiral auxiliaries: Enantioselective synthesis of chiral α-hydroxy acids

Abstract The synthesis is reported of three novel steroidal chiral auxiliaries ( 4 ) which were used to generate an α-hydroxy acid in high optical purity (90–98% ee).

An unusual dienone-phenol rearrangement product formed during the synthesis of mometasone furoate (Sch 32088)

The structure of an unusual dienone-phenol rearrangement product 4 obtained during the synthesis of mometasone furoate (Sch 32088) was assigned on the basis of NMR and x-ray crystallographic data. The mechanism of formation is discussed.

Carbon-13 nuclear magnetic resonance spectra of D-homoannulated 17-hydroxypregnan-20-ones

The 13C-NMR spectra of several groups of isomeric D-homoannulated 17 alpha-hydroxypregnan-20-ones have been recorded. The chemical shifts of the various carbon atoms have been correlated with the structures of the different isomers.

A Modified Synthesis of Retinoates

Abstract Retinoates are obtained in high yield by the reaction of N-retinylimidazolium p-toluenesulfonate with alcohols.