D 8-lactone

The effect of lactone ring-size on the inhibition was studied, for N-acetyl-)3-D-glucosaminidase from bovine epididymis, with lactones and lactone derivatives unable to undeigo ring-isomerization, by Pokomy and co-workers. From a comparison of Kj values for 2-acetamido-2-deoxy-D-glu-cono-1,5-lactone (0.45 nM) with the 1,4-lactone (4.5 fiM) and of Kj for the methyl ) -furanoside with that for the pyranose (4 mM), it was concluded that the 1,4-lactone has an 10-fold lower inhibitory potency than the 1,5-lactone. The weak inhibition by the 5,6-O-isopropylidene derivative of the... 

The results of inhibition studies with aldonolactones and 5-amino-5-deoxyaldonolactams may be summarized as follows y -D-glycosidases are inhibited by 1,5-lactones and the lactams some 100- to > 10,000-fold better than by the parent aldoses, with Kj values from 200 //Mto <0.1 nM. Al-dono-1,4-lactones are probably no better inhibitors than aldoses or polyols of comparable structure, with the possible exception s of 2-acetamido-2-deoxy-D-glucono-1,4-lactone. 

Calcium bis(2-amino-2,3,4-trideoxy-L-gZycero-pentarate) (calcium di-L-glutamate), tetrahydrate D-Arabinono-1,4-lactone Calcium L-arabinonate, pentahydrate Strontium L-arabinonate, pentahydrate Barium D-ribose 5-phosphate, pentahydrate 2-Deoxy-D-en/thro-pentose j8-DL-Arabinopyranose... 

C6H706--Na+H20 Sodium D-en/thro-hex-2-enono-1,4-lactone, monohydrate SIASCB 38 420... 

CI8H21Br07S 5-0-(p-Bromophenylsulfonyl)-2,21-0-cyclohexylidene-3-deoxy-2-C-(hydroxymethyl)-D-erythro-pentono-1,4-lactone HCDBPL 30 454... 

D-Saccharic acid 1,4-lactone (SAL 5-10 mM), a selective inhibitor of/3-glucuronidase [29], is often included in UGT reactions for improving yield. As /3-glucuronidases and UGTs have different optimal pH ranges, use of SAL in preparative-scale reactions may be avoided. 

The major pathway probably proceeds via D-galacturonic acid and L-galactono-1,4-lactone, as these are converted to L-ascorbic acid by mitochondria prepared from peas and mung beans, but neither L-gulono-1,4-... 

The following article summarizes the methods of synthesis for L-gu-lono-1,4-lactone (1), D-gulono-1,4-lactone (2), and the corresponding... 

The most efficient synthesis of L-gulono-1,4-lactone (1) entails the reduction of D-glucofuranurono-6,3-lactone (7), which can be obtained from D-glucose2 (see Scheme 1). Catalytic hydrogenation3-4 of 7 in the presence of Raney nickel afforded 1 in 81% yield. Alternatively, D-... 

A short synthesis of D-gulono-1,4-lactone (2) from the inexpensive and readily available D-xylose (34) was first reported by Fischer and Stahel,18 and subsequently by others,12,25-31 and is shown in Scheme 6. The addition of hydrogen cyanide to D-xylose (34) resulted in the formation of cyanohydrins 35 and 36 which, on hydrolysis, afforded a mixture of D-gulonic acid (4) and D-idonic acid (37). D-Gulono-1,4-lactone may be obtained in 30-33% yield by recrystallization of the reaction products. In a similar way, L-xylose (l-34) has been converted32,33 in high yield into a mixture of L-gulonic and L-idonic acids. 

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