l-Pentoses in Biological and Medicinal Applications

Synthesis and antiproliferative activities of OSW-1 analogues bearing 2-acylamino-xylose residues

“…Among them, compound 29 with the same MBz group as the natural OSW-1 showed the strongest activity and its IC 50 reached as low as 0.11 nM against Jurkat T, which is 40 times more potent than SBF-1 (2) and taxol. In fact, all the (1→3)-linked analogues (3,(29)(30)(31)(32)(33)(34) with benzoyl-type groups, including the designed photoaffinity probe 3, displayed better activities than SBF-1 (2). These comparisons clearly indicated that the replacement of the xylose residue with 2-amino-2-deoxyxylose would increase the antiproliferative activities.…”

“…22 Therefore, SBF-1 (2) has been used as an accessible alternative in biological studies. [23][24][25][26] Despite the tremendous efforts in the synthetic realm, [27][28][29][30][31][32][33] the mechanism of the antitumor activity of OSW-1 still remains elusive. Applying a synthetic probe derived at the 3-OH of the xylose moiety to the pull-down assay, Shair and co-workers disclosed that oxysterol binding protein (OSBP) and its paralog ORP4L, both of which are usually related to sterol and lipid metabolism, could be targeted by OSW-1.…”

Synthesis and Antiproliferative Activities of OSW‐1 Analogues Bearing 2”‐O‐p‐Acylaminobenzoyl Residues†

“…OSW‐1 ( 1 ) is a disaccharide saponin isolated from the bulb of Ornithogalum saundersiae by Sashida and co‐workers in the early 1990s (Figure 1). [ 1,2 ] Owing to its exceptionally strong antiproliferative activities against tumor cell lines, OSW‐1 ( 1 ) has attracted extensive researches on the synthesis, [ 3‐9 ] derivatization, and structure‐activity relationships. [ 10‐26 ] SBF‐1 ( 2 ), a synthetic analogue bearing an ester chain at C22, [ 27 ] displays comparable antitumor activities as the natural product.…”

Generation of Aptamers with an Expanded Chemical Repertoire

“…They are synthesized by l -nucleoside phosphoramidites after the corresponding d -aptamer against the mirror-image target of interest has been identified through conventional in vitro selection methods [135]. This two-step protocol is necessary since l -nucleoside triphosphates are not accepted by RNA and DNA polymerase [136], a fact that is at the origin of their use as potent antiviral agents [137]. However, progress in polymerase evolution [19,138] and the generation of ribozymes recognizing heterochiral nucleic acids or nucleotides [139], spawn hope for the discovery of enzymes capable of catalyzing the polymerization of L-nucleoside triphosphates which in turn would allow circumventing this protocol.…”