+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Synthetic application of 2 6 di deoxy glycosyl halides construction of the b a di saccharide glycoside in chromomycin a 3

, : Synthetic application of 2 6 di deoxy glycosyl halides construction of the b a di saccharide glycoside in chromomycin a 3. Chemische Berichte 113(9): 3058-3066

By photolytic deoxygenation of the diacetoxy-3,4-O-isopropylidene galacto compound 2 the 2,6-dideoxy derivative 3 is obtained. Mild acidolysis gives 4, the acetylation of which yields the monoacetates 5 and 6, and in addition the diacetate 7. Methylation of 6 using diazomethane under boron trifluoride catalysis leads to the 4-O-methyl compound 9, and with bromotrimethylsilane the 2,6-dideoxy glycosyl bromide 8 is obtained. Correspondingly, 7 gives the bromide 10 which, according to a varied glycoside synthesis procedure is condensed with the monohydroxy compound 5 to yield the .alpha.,1 .fwdarw. 3-linked disaccharide 11. By partial deacetylation the selective synthesis of 12 is achieved. The corresponding condensation of 5 and 8 allows the preparation of the disaccharide 13 which is subsequently transferred to the methyl glycoside 14 of the B-A disaccharide unit of chromomycin A3. The NMR spectral data of 14 and the disaccharide unit B-A in chromomycin A3 are consistently in agreement.


Other references

Meuwissen, J.H., 1983: Malaria vaccines in development. Nederlands Tijdschrift Voor Geneeskunde 127(38): 1729-1735

Misset J.L.; Gaget H.; Mathe G., 1983: The comparative phase 2 trials to confirm the null hypothesis their importance especially in oncology. Biomedicine & Pharmacotherapy 37(2): 58-59

Stevenson, C.W.; Halliday, D.M.; Marsden, C.A.; Mason, R., 2008: Early life programming of hemispheric lateralization and synchronization in the adult medial prefrontal cortex. Neonatal maternal separation (MS) in the rat increases the vulnerability to stressors later in life. In contrast, brief handling (H) in early life confers resilience to stressors in adulthood. Early life programming of stress reactivity may involv...

Rushing, P.A.; Winders, S.E.; Mittleman, G., 1993: Effects of phenylpropanolamine infusion and withdrawal on body weight and dietary composition in male and female rats. Male and female rats with ad lib access to separate sources of carbohydrate, fat, and protein were implanted with minipumps providing one of three dosages (0.0, 40.0, or 80.0 mg/kg/day) of phenylpropanolamine (PPA) for 2 weeks. Body weight, macron...

Lee, G-Chin.; Cushner, F.D.; Scuderi, G.R.; Insall, J.N., 2004: Optimizing patellofemoral tracking during total knee arthroplasty. Fifty-seven patients who underwent 65 primary TKAs between 1993-1994 were retrospectively studied to identify the technical challenges and pitfalls associated with patellar resurfacing and to improve patellar tracking during total knee arthroplast...

Wimmer, L.E., 1974: Neonatal hypomagnesemia: report of a case. Journal of the American Osteopathic Association 74(3): 241-243

Beroza, M.; Paszek, E.C.; DeVilbiss, D.; Bierl, B.A.; Tardif, J.G.R., 1975: A 3-layer laminated plastic dispenser of disparlure for use in traps for gypsy moths. A three-layer laminated plastic dispenser of disparlure, the sex pheromone of Lymantria (Porthetria) dispar (L.) was effective in laboratory and field trials for an entire season and emitted disparlure at a fairly uniform rate whether its ends wer...

Peters, D.A., 1988: Development of a community health intensity rating scale. The purpose of this study was to develop and validate a patient classification method for community health that would enable the categorization of patients based on their nursing care requirements. The Community Health Intensity Rating Scale (CHIR...

Mecatti, M.; Parisi, G.; Lupi, P.; Zampacavallo, G.; Giorgi, G.; Michelotti, D.; Riccio, F.; Simontacchi, C.; Tibald, E.; Poli, B.M., 2007: Welfare and quality of farmed trout fed high plant protein diets. 2: Innovative killing method effect on stress and quality indicators. Italian Journal of Animal Science 6(Supplement 1): 805

Garcia, G.; Perez, T.; Verbanck, S., 2012: Functional measurements of the peripheral airways in COPD. COPD is characterized by airflow limitation that is not fully reversible. Changes in the structure and function of the small airways (less than 2mm diameter) are now recognized to play a major pathophysiological and mechanical role in airflow limi...