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El Ashry el SH, El Tamany el SH, Fattah Mel D, et al. A new synthetic access to 2-N-(glycosyl)thiosemicarbazides from 3-N-(glycosyl)oxadiazolinethiones and the regioselectivity of the glycosylation of their oxadiazolinethione precursors. Beilstein J Org Chem. 2013;9:135-46doi: 10.3762/bjoc.9.16.
El Ashry, e. l. . S. H., El Tamany, e. l. . S. H., Fattah, M. e. l. . D., Aly, M. R., Boraei, A. T., & Duerkop, A. (2013). A new synthetic access to 2-N-(glycosyl)thiosemicarbazides from 3-N-(glycosyl)oxadiazolinethiones and the regioselectivity of the glycosylation of their oxadiazolinethione precursors. Beilstein journal of organic chemistry, 9135-46. https://doi.org/10.3762/bjoc.9.16
El Ashry, El Sayed H, et al. "A new synthetic access to 2-N-(glycosyl)thiosemicarbazides from 3-N-(glycosyl)oxadiazolinethiones and the regioselectivity of the glycosylation of their oxadiazolinethione precursors." Beilstein journal of organic chemistry vol. 9 (2013): 135-46. doi: https://doi.org/10.3762/bjoc.9.16
El Ashry el SH, El Tamany el SH, Fattah Mel D, Aly MR, Boraei AT, Duerkop A. A new synthetic access to 2-N-(glycosyl)thiosemicarbazides from 3-N-(glycosyl)oxadiazolinethiones and the regioselectivity of the glycosylation of their oxadiazolinethione precursors. Beilstein J Org Chem. 2013;9:135-46. doi: 10.3762/bjoc.9.16. Epub 2013 Jan 21. PMID: 23400104; PMCID: PMC3566832.
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Beilstein J Org Chem. 2013;9:135-46. doi: 10.3762/bjoc.9.16. Epub 2013 Jan 21.

A new synthetic access to 2-N-(glycosyl)thiosemicarbazides from 3-N-(glycosyl)oxadiazolinethiones and the regioselectivity of the glycosylation of their oxadiazolinethione precursors.

Beilstein journal of organic chemistry

El Sayed H El Ashry, El Sayed H El Tamany, Mohy El Din Abdel Fattah, Mohamed R E Aly, Ahmed T A Boraei, Axel Duerkop

Affiliations

  1. HEJ Research Institute of Chemistry, International Center for Chemical and Biological Sciences, Karachi University, Karachi, Pakistan ; Chemistry Department, Faculty of Science, Alexandria University, Alexandria, Egypt.

PMID: 23400104 PMCID: PMC3566832 DOI: 10.3762/bjoc.9.16

Abstract

Glycosylations of 5-(1H-indol-2-yl)-1,3,4-oxadiazoline-2(3H)-thione delivered various degrees of S- and/or N-glycosides depending on the reaction conditions. S-Glycosides were obtained regiospecifically by grinding oxadiazolinethiones with acylated α-D-glycosyl halides in basic alumina, whereas 3-N-(glycosyl)oxadiazolinethiones were selectively obtained by reaction with HgCl(2) followed by heating the resultant chloromercuric salt with α-D-glycosyl halides in toluene under reflux. On using Et(3)N or K(2)CO(3) as a base, mixtures of S- (major degree) and N-glycosides (minor degree) were obtained. Pure 3-N-(glycosyl)oxadiazolinethiones can also be selectively obtained from glycosylsulfanyloxadiazoles by the thermal S→N migration of the glycosyl moiety, which is proposed to occur by a tight-ion-pair mechanism. Thermal S→N migration of the glycosyl moiety can be used for purification of mixtures of S- or N-glycosides to obtain the pure N-glycosides. The aminolysis of the respective S- or N-glycosides with ammonia in aqueous methanol served as further confirmation of their structures. While in S-glycosides the glycosyl moiety was cleaved off again, 3-N-(glycosyl)oxadiazolinethiones showed a ring opening of the oxadiazoline ring (without affecting the glycosyl moiety) to give N-(glycosyl)thiosemicarbazides. Herewith, a new synthetic access to one of the four classes of glycosylthiosemicarbazides was found. The ultimate confirmation of new structures was achieved by X-ray crystallography. Finally, action of ammonia on benzylated 3-N-(galactosyl)oxadiazolinethione unexpectedly yielded 3-N-(galactosyl)triazolinethione. This represents a new path to the conversion of glycosyloxadiazolinethiones to new glycosyltriazolinethione nucleosides, which was until now unknown.

Keywords: X-ray crystallography; glycosyloxadiazolinethiones; glycosylsulfanyloxadiazoles; glycosylthiosemicarbazides; thermal rearrangement

References

  1. Eur J Med Chem. 2005 Nov;40(11):1156-62 - PubMed
  2. Carbohydr Res. 2011 Feb 1;346(2):169-76 - PubMed
  3. J Gen Microbiol. 1991 Apr;137(4):837-44 - PubMed
  4. Pharmazie. 1976;31(3):153-4 - PubMed
  5. J Org Chem. 2002 Apr 19;67(8):2577-87 - PubMed
  6. Glycobiology. 2002 Jun;12(6):69R-77R - PubMed
  7. Chem Rev. 2002 Feb;102(2):579-602 - PubMed
  8. Med Res Rev. 2005 Jan;25(1):93-131 - PubMed
  9. Carbohydr Res. 2009 Jul 6;344(10):1248-53 - PubMed
  10. Pharmazie. 1975 Nov;30(11):694-8 - PubMed
  11. Pharmazie. 2000 Apr;55(4):251-62 - PubMed
  12. Bioorg Med Chem. 2010 Nov 15;18(22):7911-22 - PubMed
  13. J Enzyme Inhib Med Chem. 2008 Feb;23(1):101-7 - PubMed
  14. Bioorg Med Chem. 2008 Oct 1;16(19):8907-13 - PubMed
  15. Acta Crystallogr Sect E Struct Rep Online. 2009 Jan 08;65(Pt 2):o242 - PubMed
  16. Bioorg Med Chem Lett. 2009 Jan 15;19(2):386-9 - PubMed
  17. Nucleosides Nucleotides Nucleic Acids. 2001 Sep;20(9):1671-82 - PubMed
  18. Org Lett. 2001 Dec 13;3(25):4019-22 - PubMed
  19. Adv Carbohydr Chem Biochem. 2004;59:135-73 - PubMed

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