Glucosides group

In these surfactants, the numerous hydroxyls of glucoside groups ensure the solubility of the whole molecule in Water. Alkylpolygiucosides show good water solubility and have their cloud points at rather high temperatures (generally above 100°C) they are only slightly sensitive to the presence of electrolytes and are only very rarely influenced by water hardness. 

The benzylidene derivative above is used, if both hydroxyl groups on C-2 and C-3 are needed in synthesis. This r/vzns-2,3-diol can be converted to the sterically more hindered a-cpoxide by tosylation of both hydroxy groups and subsequent treatment with base (N.R. Williams, 1970 J.G. Buchanan, 1976). An oxide anion is formed and displaces the sulfonyloxy group by a rearside attack. The oxirane may then be re-opened with nucleophiles, e.g. methyl lithium, and the less hindered carbon atom will react selectively. In the following sequence starting with an a-glucoside only the 2-methyl-2-deoxyaltrose is obtained (S. Hanessian, 1977). 

Substrates. The principal use for reactive dyes is dyeing textiles ceUulosics constitute the largest use. Cotton is very nearly pure cellulose, and as such has three free hydroxyl groups per glucoside unit that act as dye sites for reactive dyes. 

Kaempferol glucoside 323 a-Keto acids 249, 262, 372 3-Ketobetulic acid 59 7-Ketocholesterol 60 Ketoglutaric acid 45, 249 Keto groups, free 273 Ketohexoses 180,181 Ketone peroxides 368 Ketones 72... 

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