2816-87-7Relevant academic research and scientific papers
Synthesis of sphingosine-1-phosphonate and homosphingosine-1-phosphonate
Tarnowski, Andrej,Retz, Oliver,Baer, Thomas,Schmidt, Richard R.
, p. 1129 - 1141 (2007/10/03)
In the first approach to homosphingosine-1-phosphonate, D-glucofuranose was selectively deoxygenated at C-5. Bond cleavage between C-1 and C-2 afforded a 5-deoxy-D-threopentose intermediate. (E)-Selective Wittig reaction with a C 14-chain gave a C19-intermediate, which was readily transformed into homosphingosine. Formation of a cyclic urethane containing the 3-amino and the 4-hydroxy group of the C19-intermediate permitted regioselective introduction of the phosphonate group at C-1, thus affording the target molecule after deprotection. In a second and shorter route, C 18-sphingosine was converted to a cyclic urethane containing the 2-amino and the 3-hydroxy group of the C18-chain. C1-Chain extension by a hydroxymethyl group by introduction of cyanide led to the same C19 cyclic urethane as obtained in the first route. Similarly, the C18 cyclic urethane led to the other target molecule, namely sphingosine-1-phosphonate. The third and shortest route to homosphingosine-1- phosphonate could be based on regioselective 1-O-tosylation of 1,2,3-(trihydroxy)octadec-4-ene. Transformation into a 1,2-epoxide, then combination of C1-chain extension and introduction of a phosphonate group with methylphosphonate as reagent, and finally azide introduction, led after functional group liberation to the target molecule. As shown, also truncated derivatives are readily accessible by this route. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
Thio-sugars. I. Radical-promoted thione-thiol rearrangement of cyclic thionocarbonates: Synthesis of 5-thioglucose
Tsuda, Yoshisuke,Sato, Yoshiyuki,Kanemitsu, Kimihiro,Hosoi, Shinzo,Shibayama, Kenji,Nakao, Kayo,Ishikawa, Yuko
, p. 1465 - 1475 (2007/10/03)
The 5,6-O-thiocarbonyl-α-D-glucofuranose derivatives 2, when subjected to one of the following reactions, undergo a radical-promoted thione-thiol rearrangement to yield the 5-S-thiolcarbonates of gluco-configuration 8 as the major product. The reactions are, (A) thermolysis with a catalytic amount of tributyltin hydride and AIBN, (B) photolysis with hexabutyldistannane, and (C) thermolysis with dimethyl phosphonate and benzoyl peroxide. On the other hand, thermolysis of 2 with trialkylsilane (condition D) yielded olefins 13 as the major product. The 5-S-gluco product 8 was converted, in three steps, to 5-thioglucose (21) in 55% yield.
Conversion of thiocarbonyl into carbonyl group by O-S exchange reaction with dibutyltin oxide or bistributyltin oxide
Tsuda,Sato,Kakimoto,Kanemitsu
, p. 1033 - 1036 (2007/10/02)
Cyclic thionocarbonates and thionolactones, when heated with 1.0-1.5 mol eq of dibutyltin oxide or bistributyltin oxide in dioxane, gave the corresponding carbonates and lactones in satisfactory yields, respectively.
