851900-54-4Relevant articles and documents
Toward the synthesis of modified carbohydrates by conjugate addition of propane-1,3-dithiol to α,β-unsaturated ketones
Valdersnes, Stig,Apeland, Ingrid,Flemmen, Guri,Sydnes, Leiv K.
, p. 2099 - 2122 (2013/02/22)
Selected 5-substituted derivatives 4 of 1,1-diethoxy-5-hydroxypent-3-yn-2- one were treated with propane-1,3-dithiol under various conditions. The unprotected hydroxy ketones underwent cyclization during the dithiol addition and gave the corresponding 3-(diethoxymethyl)-2-oxa-6,10-dithiaspiro[4.5]decan- 3-ols 5 in 80-90% yield as the only products (Schemea 3 and Tablea 1). These products can be regarded as partly modified carbohydrates in the furanose form. When the benzyl-protected analogues 10-Bn of the 1,1-diethoxy-5-hydroxypent-3- yn-2-one derivatives were treated with the same dithiol, however, no cyclization occurred; instead the corresponding 3-{2-[(benzyloxy)methyl]-1,3-dithian-2-yl}- 1,1-diethoxypropan-2-one derivatives 11-Bn were formed in good yield (up to 99%; Table 4). These 1,3-dithianes were and are in the process of being converted to a number of new carbohydrate analogues, and here are reported high-yield syntheses of functionalized molecules 17 belonging to the 5,5-diethoxy-1,4- dihydroxypentan-2-one family of compounds (Table 7), via 15-Bn (Table 5) and 16-Bn (Table 6 and Scheme 8).