Isopropylidene glycerol

Glycerol, isopropylidene- also l,3-diozolane-4-methaiiol, 2,2-dimethyl-)... 

Figure 35 Two-dimensional HMBC spectra of isopropylidene glycerol recorded at 400 MHz with (A) the standard HMBC experiment, and (B) with the IMPACT-HMBC experiment. The spectra have been recorded using 128 increments, 2 transients, and a recovery delay of 0.2 s. The flip angle a was set to 130°. Measurement duration for both experiments approximately 2 min.

Deoxy-l-fluoro-L-glycerol (18) has been prepared by, among other methods, the treatment of 3,4-0-benzylidene-2,5-0-methylene-l,6-di-O-p-tolylsulfonyl-D-mannitol107 (17) with tetrabutylammonium fluoride in acetonitrile, followed by removal of the benzylidene group, periodate oxidation, reduction with borohydride, and hydrolysis. 1,6-Dideoxy-l,6-difluorogalactitol108 was obtained by treatment of 2,3 4,5-di-0-isopropylidene-l,6-di-0-(methylsulfonyl)galactitol with tetra-... 

Periodate oxidation of 5,6-O-isopropylidene-L-gulono-1,4-lactone (9a) gave 2,3-O-isopropylidene-L-glyceraldehyde in 69% yield. This compound was used to prepare 2,3-O-isopropylidene-L-glycerol and it was also condensed with amines and Wittig reagents (34). 

By-products of the above reactions are 1,2,6-tribenzoyl-D-mannitol and 1,2,6-tribenzoylsorbitol. The structure of the first was shown in two ways. Brigl and Griiner converted it to the known 1,2,5,6-tetra-benzoyl-3,4-isopropylidene-D-mannitol. Hockett and Fletcher oxidized it to dibenzoyl-D-glyceraldehyde with lead tetraacetate. This, and the fact that the rate of oxidation was like that of glycerol, not of ethylene glycol, established the structure. 1,2,6-Tribenzoylsorbitol consumed... 

In a synthesis of nucleoside analogs, the sodium salts of phthalazine-l,4-dione, phthalazin-l(2//)-one, and two pyridazin-3(2//)-ones, prepared with sodium hydride in DMF, were alkylated with ( )-2,3-0-isopropylidene-l-0-(4-toluenesulfonyl)glycerol by a nucleophilic substitution of the tosyloxy group <1999AP327>. 

O-isopropylidene-D-glycerol 22 (easily obtained from D-mannitol) as the starting material. After protection of OH-3, the acetal is removed to afford a... 

To a solution of 2,3-O-isopropyIidene-D-glyceraldehyde (12.6 g, 97 mmol) in furan (20 mL), chloroacetic acid (5.7 g, 60 mmol) dissolved in furan (20 mL) was added and the mixture was refluxed for 8 h. After 12 h at room temperature saturated aqueous NaHCOj solution (50 mL) was added and the product was extracted with ether (3 x 100 mL). Combined ether extracts were dried (MgS04), concentrated to dryness, and the residue was chromatographed on a silica gel column with light petroleum-ether-methanol (6 4 0.5) to yield If ,2ft- and lS,2ft-l-C-(2-furyl)-2,3-0-isopropylidene-glycerols 1 (95 5, 7.0 g, 36.5%). 

Irvine s first publication (1899) dealt with the rotatory powers of the optically active methoxy- and ethoxy-propionic acids prepared from lactic acid. In those early days the Purdie reaction afforded so rich a field for investigation that Irvine and his collaborators continued work on various types of hydroxy bodies in addition to the sugars. There appeared papers on the isopropylidene derivatives and methyl ethers of glycerol and mannitol, and on the chemistry of benzoin and benzoin-like materials. The constitution of the glucoside salicin was studied and its pentamethyl ether was synthesized. 

Since the synthesis of glycolipids involves the synthesis of both the lipid and the oligosaccharide portions, we shall also discuss that part of the recorded lipid synthetic work which has involved the use of carbohydrates. In fact, some of the first-recorded applications of carbohydrate molecules as chiral templates are to be found in the lipid field particularly with the use of 1,2 5,6-di-O-isopropylidene-D-mannitol [33] as a precursor of chiral glycerol derivatives for the synthesis of phospholipids and glycolipids based on glycerol and with the use of glucosamine derivatives for the synthesis of phytosphingosines [34] and since this area has not previously been reviewed, it will be treated with a more historical perspective. 

O-Isopropylidene-D-mannitol [72] is readily prepared by hydrolysis of 1,2 3,4 5,6-tri-O-isopropylidene-D-mannitol and after alkylation gives the 1,2,5,6-tetra-O-alkylmannitol on acidic hydrolysis and this is readily. converted into l,2-di-0-alkyl-L-glycerol (59). The benzyl (59, R = Bn) [73, 74], allyl (59, R = All) [75] and but-2-enyl (59, R = CH2—CH = CH—Me) [75, 76] ethers have been prepared in this way as intermediates for the synthesis of lipids. 

In the first step sodium hydride was used as a base in THF to introduce a benzyl protective group to the sn-3 position of the glycerol moiety by a Williamson ether synthesis using benzyl bromide. The benzylated solketal adduct was not isolated but introduced to deprotection of the isopropylidene... 

DIOXOLANE 2,2-DIMETHYL-4-OXYMETHYL-U-DIOXOELNE DIOXOLANE pOT) GIE GLYCEROLACETONE GLYCEROL DIMETHYL-KETAL 4-HYDROXYMETH X-2,2-DIMETHYL-l,3-DIOXOLANE ISOPROPYLIDENE GLYCEROL l,2-o-ISOPROPYLIDENE GLYCEROL SOLKETAL... 

ISOPROPYLIDENEDIPHENOL, POLYMER with 1-CHLORO-2,3-EPOXYPROPANE see IPOOOO ISOPROPYLIDENE GLYCEROL see D TI600 1,2-o-ISOPROPYLIDENE GLY CEROL see D TI600 ISOPROPYL ISOBUTYL ARSINIC ACID see IPSlOO ISOPROPYLKYANID see IJXOOO ISOPROPYL MERCAPTAN (DOT) see IMUOOO ISOPROPYL MESYLATE see IPYOOO ISOPROPYL METHANEFLUOROPHOSPHONATE see IPXOOO... 

The preparation of a number of a,b>-dimethanesuIfonates of alditols has been described. For example, by treating l,2 5,6-dianhydro-3,4-di-O-isopropylidene-D-mannitol with methanesulfonic acid, 1,6-di-0-(methylsulfonyl)-D-mannitol was formed. It is noteworthy that treatment of l,2-anhydro-3-deoxy-DL-glycerol with p-toluenesulfonic acid gave 3-deoxy-l-O-p-tolylsulfonyl-DL-glycerol and 3-deoxy-2-O-p-tolylsulfonyl-DL-glycerol. 

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