Moffatt chromatography

In connection with the synthesis of C-glycosyl compounds, Moffatt and coworkers182 developed the selective debenzoylation of 2,3,5-tri-0-benzoyl-/3-D-ribofuranosyl cyanide, which had been reported earlier163 reaction in methanolic ammonia-chloroform at 0° gave the crystalline 5 -0-benzoyl derivative in 83% yield, without recourse to chromatography. 

D-Galactose was converted by ethanethiol and hydrochloric acid into crystalline D-galactose diethyl dithioacetal, which was acetonated with acetone-zinc chloride. The product (15) was reduced to the L-fu-citol derivative (16) with Raney nickel. The overall yield of 16 was 29%, and it was characterized as the crystalline 6-p-toluenesulfonate 17. Oxidation of 16 by the Pfitzner-Moffatt reagent55 proceeded readily and, after O-deacetonation, and purification of the product by chromatography on a column of silica gel, L-fucose (18 13% overall yield from D-galactose) and L-fucitol (19 1% yield) were isolated (see Scheme 3). 

Heath D., Moffatt R. L., and Rowland S. (1995) Quantification of the C30+ fraction of North Sea gas condensates by high temperature capillary gas chromatography. Anal Proc. 32, 485-487. 

Uridine 5 -Diphosphate. Uridine 5. (trihydrogen diphosphate) UDP uridine 5 -pyrophosphate uridine-5-pyrophosphoric acid. C9HI4N20,jPj mol wt 404.18. C 26.75%, H 3.49%, N 6.93%, O 47.50%, P 15.33%. Can be isolated from calf s fiver, thymus, and yeast. The commer -cial product is derived from yeast. Pentose nucleic acids (isolated from yeast) are digested with rattlesnake venom (freed of 5 -monoesterase) and the nucleotides are separated by chromatography Cohn, Volkin, Arch, Biochem. Biophys. 35, 465 (1952) J. Biol Chem. 203, 319 (19S3). For alternate procedures see the refs under Uridine Diphosphate Glucose. Syntheses Chambers, J. Am. Chem. Soc. 81, 3032 (1959) Moffatt, Khorana, ibid. 83, 649 (1961). 

Moffatt, R, Cooper, P.A., and Jessop, K.M., Comparison of capillary electrochromatography with high-performance liquid chromatography for the analysis of pirknicarb and related compoimds, J. Chromatogr A, 855, 215, 1999. 

General. Pyridine is distilled from p-toluenesulfonyl chloride and then from calcium hydride and stored over potassium hydroxide. N,N-Di-methylformamide is distilled from calcium hydride and stored over molecular sieves. Dioxane is distilled from phosphorus pentoxide. Tri-n-butylamine, triethylamine, diphenyl phosphorochloridate, and o- and p-fluorobenzoyl chlorides are distilled before use. Tri-n-butylammonium pyrophosphate is prepared at room temperature according to the method of Moffatt and Khorana and stored at 5°. Paper chromatography is carried out by the descending technique on Whatman No. 1 paper in (A) isobutyric acid-1 M NH4OH (60 40) and (B) 1-propanol-water (7 3). Electrophoresis is carried out on Whatman No. 1 paper at pH 3.5 in 0.035 M citric acid-0.0148 M sodium citrate (1 1). Evaporations are carried out under reduced pressure at bath temperatures below 30°. Phosphate analyses of nucleoside triphosphates are performed by the method of Lowry and Lopez after treatment of approximately 1 / mole of these compounds for 60 min at 22° in 1 ml of Tris chloride at pH 10.4 containing 0.02 mg of alkaline phosphatase of calf intestinal mucosa (type VII, Sigma Chemical Co.). 

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