866394-64-1Relevant articles and documents
A comparative study of the neutral and acidic polysaccharides from Allium macrostemon Bunge
Zhang, Zhanjun,Wang, Fuhua,Wang, Mingchun,Ma, Liping,Ye, Hong,Zeng, Xiaoxiong
, p. 980 - 987 (2015/01/09)
Neutral and acidic polysaccharides, named AMP40N and AMP40S respectively, were isolated and purified from the dried bulbs of Allium macrostemon Bunge. Both of them showed a single and symmetrically sharp peak, indicating they were homogeneous polysaccharides. Molecular weights of AMP40N and AMP40S were determined to be 18.2 and 105.1 kDa, respectively. AMP40N was composed of arabinose and glucose, while AMP40S was composed of rhamnose, arabinose, glucose and galactose and a certain amount of uronic acid. FT-IR, periodic acid oxidation, Smith degradation, methylation and GC-MS analysis revealed that non-reducing terminal and →2,6)-Glc-(1→ existed in AMP40N and AMP40S. The glycosidic linkage of arabinose in AMP40N was →2)-Ara-(1→, whereas it was Ara-(1→ in AMP40S. AMP40S had (1→2)-linked l-rhamnose residue. Both AMP40N and AMP40S exhibited strong anti-tumor potential against human gastric carcinoma cells BGC-823, in particular, AMP40S presented significantly higher inhibitory rate of 85.94% than AMP40N of 52.63%.
Efficient asymmetric organocatalytic formation of erythrose and threose under aqueous conditions
Burroughs, Laurence,Vale, Matthew E.,Gilks, James A. R.,Forintos, Henrietta,Hayes, Christopher J.,Clarke, Paul A.
supporting information; experimental part, p. 4776 - 4778 (2010/09/05)
Esters of proteinogenic amino acids efficiently catalyse the formation of erythrose and threose under aqueous conditions in the highest yields and enantioselectivities yet reported. Remarkably while esters of (l)-proline yield (l)-carbohydrates, esters of (l)-leucine and (l)-alanine generate (d)-carbohydrates, offering the potential to account for the prebiotic link between natural (l)-amino acids and natural (d)-sugars.
EQUILIBRATION OF ALDITOL ANHYDRIDES IN ACETIC ACID
Wisniewski, Andrzej,Gajdus, Jerzy,Sokolowski, Janusz,Szafranek, Janusz
, p. 11 - 20 (2007/10/02)
Dehydration of pentitols in acetic acid containing an acidic catalyst parallels that in aqueous sulfuric acid; 1,4(2,5)-dehydration occurs with inversion of configuration at C-2 or C-4.Acetylated alditols undergo similar processes via intermediates having free hydroxyl groups.Configurational inversion of 1,4- or 1,5-anhydroalditols is attributed to intermediate acyloxonium ions that are also proposed as intermediates in the structural isomerisation.Drastic treatment of each alditol gives equilibrium mixtures.The equilibrium concentrations are used to calculate free-energy differences.
