3-deoxy-, 3-fluoro preparation

Also prepared during this work were the previously unknown deoxy fluoro cellobioses 28 and 29. 

Acetalated myo-inositol derivatives have been converted by standard reactions into intermediates required for the total synthesis of sugarotoxin and some of its analogues, which are 6-0-acyl derivatives of myo-inositol.Quebrachitol reacts with DAST to a deoxy-fluoro derivative which, on demethylation, gave the fluoro-inositol (54), a cellular replication inhibitor.Deoxy-fluoro-myo-inositols have been prepared, and their behaviour as substrates for phosphatidyl-inositol synthetase has been reported. 2-C-fluoromethyl-myo-inositol (55) has been prepared conventionally from an exocyclic oxiran precursor. 

Carbohydrates. Relatively few pentose or hexose derivatives have been prepared as potential antitumor agents during the reporting period. In a series of deoxy-fluoro-D-glucopyranoses, only 6-deoxy-6-fluoro-D-glucose inhibited (up to 90%)... 

The 4-triflates 277, 279, and 281 of benzyl 2,3-anhydro-o -D- and -) -L-ri-bopyranosides and -a-D-lyxopyranoside gave, - readily, on reaction with BU4NF [CgHg (24 h) or MeCN (5-8 h), r.t.], the respective 2,3-anhydro-4-deoxy-4-fluoro derivatives 278,280, and 282 in good yields. The conformation ( //s) of the starting compounds remained the same after fluorination. Methyl 2,3-anhydro-4-deoxy-4-fluoro-a-L-lyxopyranoside (284, 86%) was prepared from the 4-triflate 283 by treatment with EtjN- 3HF (CH2CI2-EtjN, 40°, 5 h). 

Deoxy-5-fluoro-D-glucose and -L-idose were synthesized from 1,2-(9-isopropylidene-a-D-glucofuranurono-6,3-lactone (285). Treatment of l,2-0-isopropylidene-5-0-triflyl-a-D-gluco- (286 prepared from 285) and -) -L-ido-furanurono-6,3-lactones (289 prepared from 288), with BU4NF... 

Deoxy-6-fluoro-L-ascorbic acid ° (314) was prepared from methyl 2,3-<9-isopropylidene-6-0-tosyl-a-L-gulosonate (313) by reaction with KP followed by isomerization of the product (with H" " cation-exchange resin). 

Benzyl 2-acetamido-6-0-benzyl-2,4-dideoxy-4-fluoro-a-D-glucopyrano-side and the corresponding free sugar were prepared from benzyl 2-acet-amido-3-0-allyl-6-0-benzyl- (or -3,6-di-0-benzyl)-2-deoxy-a-D-galacto-pyranoside by treatment with DAST (in diglyme). 

Trideoxy-2,3,4-trifluoro-D-galacto- and -gluco-pyranosyl derivatives 391 and 392 have been prepared from l,6-anhydro-4-(9-benzyl-2-deoxy-2-fluoro-/ -D-glucopyranose (385) by use of DAST, through several intermediates, as shown [385 386,10% 387- 388,72% 389 390,90% refl. toluene (for 385) or dichloromethane (for 387 and 389), 24 h]. 

VlL-l-Deoxy-l-fluoro-myo-inositol (393) and (+)-lD-l-deoxy-l-fluoro-m> oinositol (394) have been prepared from myo-inositol through multi-step reactions involving DAST treatment. 

Deoxy-3-fluoro-D-glucose (25%) and -mannose (40%) were prepared from 2-deoxy-2-fluoro-D-arabinose by a chain-extension reaction (cyanohydrin synthesis). Likewise, 4-deoxy-4-fluoro-D-glucose ° (27%) and -mannose (45%) were prepared from 3-deoxy-3-fluoro-D-arabinose. ... 

Deoxy-4-fluoro-D-fructose (552) was prepared (59%) by fermentation of 3-deoxy-3-fluoro-D-mannitol with Gluconobacter oxydans. The structure of 552 (fi-T) form) was confirmed by the n.m.r. spectrum, which resembles that of 4-deoxy-4-fluoro-Q -D-sorbopyranose (553) 552 was identical with one of the products obtained from the oxirane-ring opening of 3,4-anhy-dro-l,2-0-isopropylidene- -D-tagatopyranose with KHFj. 

Deoxy-2-[ F]fluoro-3-(9-methyl-D-glucopyranose was prepared by the reaction of methyl 4,6-0-benzylidene-3-0-methyl-2-0-triflyl-) -D-manno-pyranoside (159) with CsH F2, and the possibility of its use as an imaging agent was examined." ... 

Deoxy-2-[ F]fluoro-D-mannose ( F-2DFM) was prepared through treatment of 201 (see Section 11,2) with F-Bu4NF(MeCN, 75°, 30 min) or K F crown ether, as reported for the cold synthesis. F-2DFM was also prepared from methyl 4,6-di-0-acetyl-3-C>-benzoyl-2-C>-triflyl-a-D-glu-copyranoside with amino(polyether)-supported, carrier-free [ F]fluoride. 

Deoxy-2-[ F]fluoro-D-galactose can be prepared through an addition reaction to tri-O-acetyl-D-galactal (465), but better through Sn2 reaction (K F-Kryptofix 222 in MeCN) of methyl 3,4-0-isopropylidene-2-0-triflyl-6-0-trityl-y -D-talopyranoside (220 see Section 11,2), according to the cold synthesis. 

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