6-De­oxy-α-l-talopyran­ose

X-ray crystallography showed that the title compound, C6H12O5, crystallizes in the α-pyran­ose form with the six-membered ring in a chair conformation. The crystal structure exists as a three-dimensional hydrogen-bonded network of mol­ecules with each mol­ecule acting as a donor and aceptor for four hydrogen bonds. The absolute configuration was determined by the use of l-fucose as starting material

1-De­oxy-d-galactitol (l-fucitol)

1-De­oxy-d-galactitol, C6H14O5, exists in the crystalline form as hydrogen-bonded layers of mol­ecules running parallel to the ac plane, with each mol­ecule acting as a donor and acceptor of five hydrogen bonds

6-Azido-6-de­oxy-α-l-galactose (6-azido-l-fucose) monohydrate

Although 6-azido-6-de­oxy-l-galactose in aqueous solution is in equilibrium between the open-chain, furan­ose and pyran­ose forms, it crystallizes solely as 6-azido-6-de­oxy-α-l-galactopyran­ose monohydrate, C6H11N3O5·H2O, with the six-membered ring adopting a chair conformation. The structure exists as hydrogen-bonded chains, with each mol­ecule acting as a donor and acceptor of five hydrogen bonds. There are no unusual crystal packing features and the absolute configuration was determined from the use of 1-azido-1-de­oxy-d-galactitol as the starting material

2,6-Dide­oxy-2,6-imino-l-glycero-d-ido-heptitol

The title mol­ecule, C7H15NO5, the major product from selective enzymatic oxidation followed by hydrogeno­lysis of the corresponding azido­heptitol, was found by X-ray crystallography to exisit in a chair conformation with three axial hydroxyl groups. One of the hydroxymethyl groups is disordered over two sets of sites in a 0.590 (3):0.410 (3) ratio. In the crystal, O—H⋯O, O—H⋯(O,O), O—H⋯N and N—H⋯O hydrogen bonding occurs

A Novel Rare Sugar Inhibitor of Murine Herpes Simplex Keratitis.

Purpose To determine the therapeutic efficacy of a novel rare sugar, L-psicose, for the treatment of HSV-1 induced herpetic stromal keratitis (HSK) in a mouse eye model. Methods One rare sugar L-psicose was assayed for HSV-1 inhibition of in vitro virus adsorption. The IC50 and IC90 values of L-psicose were determined using plaque reduction assay (PRA) in CV-1 cell. Female Balb/c mice were corneally infected with HSV-1, strain KOS-GFP; A topical eye drop treatment of L-psicose was started 24 h after infection and continued four times daily for ten consecutive days. The severity of HSK was monitored by slit lamp examination in a masked fashion and Infectious HSV-1 shedding was determined by PRA. Results L-psicose was found to have anti-viral activity in vitro at an IC50 dose of 99.5 mM and an IC90 dose of 160 mM. Topical eye drop treatment with 200 mM L-psicose in PBS solution significantly reduced the severity of HSK compared to the mock treatment group. The in vivo mouse ocular model results of L-psicose therapy correlated with accelerated clearance of virus from eye swabs. Conclusion The results suggest that topical treatment with rare sugar L-psicose has efficacy against HSK through inhibition of HSV-1

Structure of l-rhamnose isomerase in complex with l-rhamnopyranose demonstrates the sugar-ring opening mechanism and the role of a substrate sub-binding site

Abstractl-Rhamnose isomerase (l-RhI) catalyzes the reversible isomerization of l-rhamnose to l-rhamnulose. Previously determined X-ray structures of l-RhI showed a hydride-shift mechanism for the isomerization of substrates in a linear form, but the mechanism for opening of the sugar-ring is still unclear. To elucidate this mechanism, we determined X-ray structures of a mutant l-RhI in complex with l-rhamnopyranose and d-allopyranose. Results suggest that a catalytic water molecule, which acts as an acid/base catalyst in the isomerization reaction, is likely to be involved in pyranose-ring opening, and that a newly found substrate sub-binding site in the vicinity of the catalytic site may recognize different anomers of substrates

6-Deoxyhexoses froml-Rhamnose in the Search for Inducers of the Rhamnose Operon: Synergy of Chemistry and Biotechnology

In the search for alternative non‐metabolizable inducers in the l ‐rhamnose promoter system, the synthesis of fifteen 6‐deoxyhexoses from l ‐rhamnose demonstrates the value of synergy between biotechnology and chemistry. The readily available 2,3‐acetonide of rhamnonolactone allows inversion of configuration at C4 and/or C5 of rhamnose to give 6‐deoxy‐d ‐allose, 6‐deoxy‐d ‐gulose and 6‐deoxy‐l ‐talose. Highly crystalline 3,5‐benzylidene rhamnonolactone gives easy access to l ‐quinovose (6‐deoxy‐l ‐glucose), l ‐olivose and rhamnose analogue with C2 azido, amino and acetamido substituents. Electrophilic fluorination of rhamnal gives a mixture of 2‐deoxy‐2‐fluoro‐l ‐rhamnose and 2‐deoxy‐2‐fluoro‐l ‐quinovose. Biotechnology provides access to 6‐deoxy‐l ‐altrose and 1‐deoxy‐l ‐fructose

Potent Inhibitory Effects of D-tagatose on the Acid Production and Water-insoluble Glucan Synthesis of Streptococcus mutans GS5 in the Presence of Sucrose

We examined and compared the inhibitory effects of D-tagatose on the growth, acid production, and water-insoluble glucan synthesis of GS5, a bacterial strain of Streptococcus mutans, with those of xylitol, D-psicose, L-psicose and L-tagatose. GS5 was cultured for 12h in a medium containing 10ｵ (w/v) of xylitol, D-psicose, L-psicose, D-tagatose or L-tagatose, and the inhibitory effect of GS5 growth was assessed. Each sugar showed different inhibitory effects on GS5. Both D-tagatose and xylitol significantly inhibited the acid production and water-insoluble glucan synthesis of GS5 in the presence of 1ｵ (w/v) sucrose. However, the inhibitory effect of acid production by D-tagatose was significantly stronger than that of xylitol in presence of sucrose

Macroscopic findings for breast VAB specimens

Purpose : Ultrasound-guided breast tissue biopsy is an essential technique for diagnosing breast disease, but sample errors reduce its accuracy. This study investigated whether the histopathological results can be inferred from the macroscopic findings for Ultrasound-guided breast Vacuum Assisted Biopsy (VAB) specimens. Methods: Biopsy specimens from 101 patients who underwent mammary gland VAB were photographed with a smartphone, and the relationships between the macroscopic findings and the pathological results were examined. Results : A significant difference was observed with regard to the presence / absence of turbidity: malignancy was detected in 33 / 37 (89%) specimens with turbidity and in 2 / 47 (4%) cases without turbidity (p < 0.001). A significant difference was also observed regarding the surface properties : malignancy was detected in 14 / 70 (19%) smooth specimens and in 24 / 29 (83%) rough specimens (p < 0.001). Also, malignancy was detected in 11 / 13 (85%) specimens with white spots, and the difference was significant (p < 0.001). In addition, the characteristics of intraductal papilloma, fibroadenoma, and mastopathy could be confirmed by macroscopic findings. Conclusions : When needle–biopsy of a lesion that is targeted for resection yields macroscopic findings that match the predicted histopathological findings, it can be thought that the biopsy had been properly performed. This means that false–negatives due to poor specimens can be prevented