9 G G was also found to be superior to the older methods en~ploying zinc and acetic acid (7) or zinc and alcoholic sodium hydroxide (8). The new isobenzofurans that \\-ere prepared are listed in Table I I I. E X P E R I M E X T A L Melting points were determined on a Thomas-Hoover melting point apparatus and are uncorrected. Microanalyses were carried out by Alfred Bernhardt, Miilheim, Germany. Infrared spectra were obtained on a Perkin-Elmer infracord, 0.25y0 in ICBr. Ultraviolet and visible spectra were obtained on a PerkinElmer model 202 spectrophotorneter, 1 cm cells, 95y0 ethanol as solvent.The 2-benzoylbenzophenones (I) were prepared by the method of Vingiello eL al. (3). The 1,4-diarylphthalazines (11) were prepared by the method of Blicke and Swisher (9). The 1,3-diarylisobenzofurans (111) were prepared by the method of Cava et al. (6).

A B S T R A C T A neutral extracellular glucan ([a]nZ3 +18g0) was produced i n 127, yield b y Pullularia pullulans (de Bary)The yeast-like fungus Pullularia pullulans produces a mixture of glucose-containing extracellular polrsaccharides (I). I t has been shown (2, 3) that one of the polysaccharides formed by the fungus from glucose as the carbon source is a linear glucan ("pullulan") having [a], +192" and coinposed of approximately 300 a-D-glucopyranose units linked -(1 + 4) and (1 -+ 6) in the ratio 3:2. Bouveng et al. (4) have examined the polysaccharides produced by Pullularia pullulans from various sugar substrates, and have found that a sucrose medium yielded a linear glucan having [a], +190° and consisting of more than 250 units linked a ( l -+ 4) and a ( 1 -+ 6) in the ratio 2:l. A small amount (1-27,) of glucose remaining after periodate oxidation of the polysaccharide suggested that (1 -+ 3) linkages might be present, although this was not supported by methylation data. No evidence for the presence of (1 -+ 3) linkages ilT the polysaccharide produced from glucose was reported in earlier work (2, 3). The present publication reports the results obtained from partial acid hydrolysis and froin periodate oxidation of the glucan produced by Pullularia pullulans grown on glucose.The growth conditions of the organism and the method of recovery used for the preparation of the polj~saccharide in the present work favored isolation of the water-soluble glucan to the exclusion of the more insoluble jelly-like polysaccharide which adheres to the mycelium (1). The polysaccharide showed a single symmetrical peak on electrophoresis in borate and acetate buffers, gave no precipitate with Cetavlon, and showed no carboxyl absorption in its infrared spectrum. This evidence showed that the polysaccharide was homogeneous and contained no acid groups. Bouveng et al. (4) found that yields of polysaccharide were increased and that formation of uronic acid and other hexose units was diminished when the organism was grown on glucose rather than other sugar substrate (except for sucrose).Infrared spectroscopy of the polysaccharide showed strong absorption a t 850 cm-l,

3-Amino-3-deoxy-D-ribose and D-ribose were prepared from a derivative of D-xylose. 1,2-0-Isopropylidene-5-0-triphenylmethyl-a-D-xylofuranose (2) was oxidized by dimethyl sulfoxide -acetic anhydride to 1,2-O-isopropylidene-5-O-triphenylmethyl-a-~-erythro-pentofuranos-3-uose (3). The oxime (4) of this 3-keto sugar derivative was reduced with lithium aluminium hydride to 3-amino-3-deoxy-l,2-0-isopropylidene-5-0-triphenylmethyl-a-D-ribofuranose (5), isolated as the acetamido derivative (6). Hydrolysis yielded 3-amino-3-deoxy-D-ribose hydrochloride. 3 was reduced by sodium borohydride to 1,2-0-isopropylidene-5-0-triphenylmethyl-a-D-ribofuranoe (7), which yielded D-ribose on hydrolysis.Canadian Journal of Chemistry, 46, 1586Chemistry, 46, (1968 In recent years many unusual amino and interest because it occurs in puromycin (2) and deoxy sugars have been identified as components in 3'-amino-3'-deoxyadenosine (3). Puromycin, of a number of antibiotic substances (1). One of which has been identified as 6-dimethylamino-9-these sugars, 3-amino-3-deoxy-D-ribose, is of For personal use only.NOTES furanosyl]purine (4), has become an important biochemical tool since its inhibitory effect on protein biosynthesis was demonstrated (5). Both nucleosides exhibit significant antitumor activity (6, 7) and 3-amino-3-deoxy-D-ribose has been described as an intermediate useful for the preparation of compounds antagonistic to vitamins B, and B,, (8). Numerous synthetic 3'-amino-3'-deoxynucleosides have been reported (9)(10)(11)(12)(13)(14).Several procedures have been published for the synthesis of 3-amino-3-deoxy-D-ribose. The first two are similar in principle. Ammonolysis of 2,3-anhydropentose derivatives yields intermediate 3-acetamido-3-deoxypentose compounds; the required configurational inversion of these is obtained by the attack of the acetamido group on a neighboring trans-methylsulfonate (15, 16). Another method (17) depends on the inversion which takes place when the p-tolylsulfonoxy group of 1,2 ;5,6-di -0-isopropylidene-3 -0 -ptolylsulfonyl-a-D-glucofuranose undergoes hydrazinolysis. Reduction of the hydrazino compound yields a derivative of 3-amino-3-deoxy-D-allose which is then converted to 3-amino-3-deoxy-D-ribose via periodate oxidation and borohydride reduction. A fourth procedure (18) is shorter and more direct than the others. Periodate oxidation of methyl P-D-xylopyranoside followed by treatment of the intermediate dialdehyde with nitromethane and sodium yields the sodium salt of methyl 3-aci-nitro-3-deoxy-P-D-ribopyranoside. This is converted to the free nitropentoside with potassium bisulfate and anhydrous sodium sulfate in a ball-mill. Methyl 3-amino-3-deoxy-P-D-ribopyranoside is obtained by hydrogenation of the nitropentoside with platinum catalyst in the presence of hydrochloric acid.The present commuilication reports a new and simple method for preparing 3-amino-3-deoxy-Dribose. 1,2-0-Isopropylidene-E-D-xylofuranose (I), readily obtained by hydrolysis of 1,2;3,5-di-0-isopr'opylidene-a-D-xylofuranose (19), was...

L-Glucurone (2) was readily prepared on a small scale by treatment of D-glycero-D-gulo-heptonolactone (1) with a molar equivalent of periodic acid; thin-layer chromatography was used for its isolation. On a larger scale pure crystalline L-glucurone was obtained in over 80% yield from 3,5;6,7-di-O-isopropylidene-~-g~ycero-~-gufo-heptonoactone (4) in two steps consisting of concomitant hydrolysis and oxidation of 4 with periodic acid followed by treatment of the intermediate oxidation product with trifluoroacetic acid. L-Glucose was prepared from L-glucurone by borohydride reduction and hydrolysis of the 1,2-0-isopropylidene derivative. Since 1 was derived from D-glucose, the result of this series of reactions was the conversion of D-glucose into its enantiomer L-glucose.Canadian Journal of Chemistry, 47, 3931 (1969) The first chemical synthesis of a uronic acid aldonolactone. The procedure has been used on was carried out in 1890 by Fischer who obtained two previous occasions. Woods and Neish treated D-glucuronic acid and its lactone by reduction of 2-C-hydroxymethyl-D-glucono-1,4-lactone with D-glucaro-l,4-lactone with sodium amalgam in an equimolar amount of periodate and obtained acid solution (1). Niemann and Link in 1934 used 4-C-hydroxymethyl-L-xyluronolactone, which the same procedure for the enantiomer L-glucuronic acid (2). The starting material, L-glucaro-1,4-lactone, was prepared via calcium L-glucarate from nitric acid oxidation of D-gulono-1,4-lactone. The yield of L-glucurone (2), the form in which the L-glucuronic acid was isolated, was about 1% based on calcium L-glucarate. L-Glucuronic acid is of interest because it has been reported to occur naturally, along with D-glucuronic acid, as a metabolic product of the action of rat kidney enzymes on inositol (3). Other workers, however, were unable to detect L-glucuronic acid and have found that inositol is converted into D-glucuronic and L-gulonic acids (4). This discrepancy has not been explained.The biochemical and pharmacological importance of D-glucuronic acid (5) has led to a thorough investigation of methods for its synthesis, especially those based on oxidation of suitably protected D-glucose derivatives (6). Undoubtedly these procedures can be applied to the synthesis of L-glucuronic acid from L-glucose, but this is not attractive because L-glucose is not readily available. The present publication describes a facile synthesis of L-glucurone (2) from D-glycero-D-gulo-heptonolactone (I), a starting material easily prepared from ordinary D-glucose by the Kiliani synthesis (7). This work is an example of the application of a simple and general method for the preparation of uronic acids directly as their lactones, namely selective periodate cleavage of the exocyclic glycol system of an crystallized as the acid (8). Similarly, Hulyalkar and Perry oxidized D-galactono-l,4-lactone to obtain L-lyxuronic acid, isolated as methyl L-lyxuronate (9). Essentially, oxidative removal of the primary alcohol of an aldonolactone results in inversion of the mol...

L-Iduronic acid is a major constituent of the anticoagulant heparin according to recent evidence obtained from chemical degradation studies (1) and by 220 MHz p.m.r. spectroscopy (2). Contrary to earlier work (3-6), D-glucuronic acid appears to be a minor rather than a major component of the mucopolysaccharide. The p.m.r. data at 220 MHz confirm that L-idosyluronic acid residues occur also in dermatan (chondroitin sulfate B) and possibly heparitin (2).Synthetic L-iduronic acid is not readily available. It has been prepared by application of the cyanohydrin synthesis to 1,2-0-isopropylidenea-D-xylo-pentodialdo-1 ,Cfuranose, the product of periodate oxidation of 1,2-0-isopropylidenea-D-glucofuranose (7). In this procedure 1,2-0-isopropylidene-P-L-idofuranurono-6,3-lac is separated from the co-product, 1,2-0-isopropylidene-a-D-glucofuranurono-6,3-lactone, by columnchromatography onclay. Reported recently is an alternative synthesis also based on chain extension of 1 ,2-0-isopropylidene-a-D-xylo-pentodialdo-1,Cfuranose (8). The xylo derivative, or its 3-benzyl ether, is ethynylated to yield a mixture of 5-epimeric, 7-carbon acetylenic sugars. The epimeric heptynes are separated by fractional distillation or by silica gel chromatography and converted by ozonolysis into derivatives of D-glucuronic and L-iduronic acids.For many purposes in investigations of natural polymers containing L-iduronic acid, the enantiomer would serve as a reference compound. as in the preparation of L-glucurone (9). D-Idurone was isolated by preparative paper chromatography. On a millimolar scale, the yield was around 50%. A useful crystalline derivative is the dibenzyl dithioacetal. To minimize degradation of the uronic acid, it was advantageous to use trifluoroacetic acid instead of hydrochloric acid as a catalyst for thioacetalation.The preparation of D-idurone was further simplified by oxidizing a mixture of D -~~Y c~~o ido-heptonolactone and D-glycero-D-gulo-heptonolactone, thus avoiding isolation of pure ido starting material. The mixture of heptonolactones was easily obtainable either from D-glucose by the cyanohydrin synthesis (10) or by epimerization of commercially-available D-glycero-D-guloheptonolactone with pyridine. After periodate oxidation of the mixed lactones, both D-idurone and L-glucurone were isolated by paper chromatography in butanol-ethanol-water (5 :2: 1 v/v), a solvent system in which they are widelyseparated.The straightforward resolution of D-idurone Can. J. Chem. Downloaded from www.nrcresearchpress.com by 54.245.55.244 on 05/11/18For personal use only.

not available

Monosaccharides with a cis-configuration at C-2 and -3 readily undergo inversion at C-2 in an acetolysis medium composed of acetic acid, acetic anhydride, and sulfuric acid. The acetolysis-inversion reaction has been carried out with 2,3;5,6-di-0-isopropylidene-D-gulofuranose, 2,3;6,7-di-0-isopropylidene-D-glycero-D-gulo-heptose, 2,3-0-isopropylidene-D-ribose, D-ribose, and D-mannose using chromatography for isolation of the deacetylated epimeric products. The reaction requires a medium with a high concentration of acetic acid (ca. 90%) and appears to take place only with furanose structures. Inversions observed with the unsubstituted pyranoses D-ribose and D-mannose probably occur because of tautomerization to furanose forms. The epimerization proceeds in the direction which yields a smaller number of cis-oriented groups at C-2, -3, and -4 of the furanose forms of monosaccharides.

No abstract