74281-90-6Relevant academic research and scientific papers
ACYCLIC-SUGAR 6-CHLOROPURINE NUCLEOSIDE ANALOGS DERIVED FROM D-ALDOHEXOSES HAVING THE D-erythro STEREOCHEMISTRY AT C-4 AND C-5
Horton, Derek,Liu, Charng-Ming
, p. 55 - 70 (2007/10/02)
1-(6-Chloropurin-9-yl)-1-S-ethyl-1-thio-D-mannitol, 1-(6-chloropurin-9-yl)-1-S-ethyl-1-thio-D-altritol, and 1-(6-chloropurin-9-yl)-3-deoxy-1-S-ethyl-1-thio-D-arabino-hexitol were prepared by a new method of direct coupling of an acyclic-sugar derivative to the base.The coupling products were obtained as pairs of 1'-epimers.The epimeric mixture of D-manno derivatives was resolved by liquid chromatography, and the products were fully characterized.Glycosylation at N-9 of the purine ring was established by u.v. and (13)C-n.m.r. spectroscopy, and the chirality at C-1' by circular dichroism measurements.The conformations of the acyclic-sugar chains in solution were also examined.
ACYCLIC-SUGAR PURINE NUCLEOSIDES DERIVED FROM D-GLUCOSE: STEREOCHEMICAL CORRELATIONS IN ACYCLIC-SUGAR DERIVATIVES UNEQUALLY SUBSTITUTED AT C1
Blieszner, Kathleen C.,Horton, Derek,Markovs, Robert A.
, p. 241 - 262 (2007/10/02)
Condensation of 2,3,4,5,6-penta-O-acetyl-1-bromo-1-S-methyl-1-thio-D-glucitol (1) with 6-chloro-9-(chloromercuri)purine gave 49percent of crystalline, levorotatory (1S)-2,3,4,5,6-penta-O-acetyl-1-(6-chloropurin-9-yl)-1-S-methyl-1-thio-D-glucitol (3), together with a smaller proportion of the syrupy, dextrorotatory (1R) isomer.Thiourea converted 3 into its 6-mercaptopurine analog, whose O-deacetylated derivative could be S-methylated to the corresponding 6-(methylthio)purin-9-yl analog: all compounds in this sequence were crystalline and were the pure (1S) isomers, as were the corresponding 1'-S-ethyl derivatives prepared by a similar route.Crystal-structure analysis of the O-deacetylated derivative of the 1'-S-ethyl analog of 3 established the relative stereochemistry of the ethyltio group, permitting assignment of the (1S) absolute stereochemistry to this compound and thus to all compounds in the sequence starting from 1, including the previously described, crystalline, levorotatory 1-(1,6-dihydro-6-thioxopurin-9-yl)-1-S-ethyl-1-thio-D-glucitol, whose chirality at C-1 had not hitherto been established.The close similarity of the chiroptical properties of the crystalline 1'-S-methyl derivatives to those of their 1'-S-ethyl counterparts permitted firm attribution of (1S) chirality to the former series also.Conformational studies showed that all of the derivatives have the sugar chain in a non-extended (sickle) conformation.
