R-C-H Branch

Yoshimura, M. Matsuzawa, K.-I. Sato, and M. Funabashi, Ghent. Letters, 1977, 1403. 

Nieuwenhuis and J. H. Jordaan, Tetrahedron Letters, 1977, 369. M. M. A. Abdel-Rahman, Bull. Chem. Soc. Japan, 1977, 50, 1619. 

The dialdehydes from periodate oxidation of methyl 4,6-0-benzylidene-a-and -p-D-glucopyranoside reacted with appropriate Wittig reagents to give such dienes as (400) that afforded cyclized products [e.g. (401)] with nitromethane by a double Michael condensation, whereas only one of the olefinic linkages was attacked, without cyclization, with ethyl cyanoacetate and malononitrile. Details of the reactions of these dialdehydes with nitroalkanes (see Vol. 8, p. 108), ethyl cyanoacetate (see VoL 8, p. IlOX and other carbanions to give various branched-chain heptoseptanosides have also been reported.  

Methyl 2,3-anhydro-4-0-benzyl-P-L-ribopyranoside reacted with dimethyl-magnesium in ethanol to give methyl 4-0-benzyl-3-deoxy-3-C-methyl-p-L-xylopyranoside (402).  

A variety of approaches to deoxy branched-chain sugars have been reported. 

Michael addition to levoglucosenone with various carbon nucleophiles under base or bis (2,4-pentanedionate)-nickel(II) catalysis gave a series of 4-C-alkyl-4-deoxy branched-chain hexosuloses (30) 2-methylcyclohexanone yielded both its 2- and 6- substituted 

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Characterization of Natural Products Compounds with aui R -C-0R Branch Compounds with am R-C-N Branch Compounds with an R-C-H or R-C-R Breinch... 

Sugars Containing an R-C-OH Branch, 2 Compounds Containing an R-C-H or R -C-R Branch Sugars Containing an R-C-N Branch General... 

CAS 108419-35-8 EINECS/ELINCS 283-740-9 Synonyms Acetic acid, C11-14-branched alkyl esters, C13-rlch Formula CH3CO2R, where R = C-H, (primarily)... 

In the group of nonfluorescing alkanes the lifetimes are very short, x < 0.3 nsec an upper limit of i < 3 x 10 sec is estimated. The absence of fluorescence for these compounds may have two causes the low R, i.e., low rate coefficient of the Si Sq radiative transition and the short lifetime, i.e., the very fast chemical decomposition. In the C5 and C7-C10 cycloalkanes the ring strain, which is mainly caused by the repulsive interaction of their unfavorably displaced H atoms, may enhance the rate coefficient of the chemical decay by C-H decompositions. In the excited sates of the geminally branched... 

Zhao, Z., R. E. Stickel, and P. H. Wine, "Branching Ratios for Methyl Elimination in the Reactions of OD Radicals and Cl Atoms with C H, SC HChem. Phys. Lett., 251, 59-66(1996). 

Heindel, J.J. Powell, C.J. (1992) Phthalate ester effects on rat Sertoli cell function in vitro effects of phthalate side chain and age of animal. Toxicol appl. Pharmacol, 115, 116-123 Hellwig, J., Freudenberger, H. Jackh, R. (1997) Differential prenatal toxicity of branched phthalate esters in rats. Food Cosmel Toxicol, 35, 501-512 Hildebrand, H., Schmidt, U., Kempka, G, Jacob, R., Ahr, H.J., Ebener, C., Goretzki, RE. Bader, A. (1999) An in-vitro model for peroxisome proliferation utilizing primary hepatocytes in sandwich culture. Toxicol. In Vitro, 13, 265-273... 

Colditz, G.A., Branch, L.G., Lipnick, R.J., Willett, W.C., Rosner, B., Posner, B.M., and Hennekens, C.H. 1985. Increased green and yellow vegetable intake and lowered cancer deaths in an elderly population. Am. J. Clin. Nutr. 41, 32-36. 

Figure 6.25 shows the 3q band of HCN in which v3 is the C—H stretching vibration. The transition is of the Z+-Z+ type showing clear P- and i -branch structure like a diatomic molecule. However, unlike a diatomic molecule, there are two hot bands, involving lower states in which the low-wavenumber bending vibration v2 is excited, overlapping 3q. One band shows a P,Q and R branch with the band centre at about 3292 cm 1 and the other a P and an R branch with the band centre at about 3290 cm-1. 

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