287119-15-7Relevant academic research and scientific papers
Total synthesis and the anticancer activity of (+)-spisulosine
Fabi?íková, Milica,Martinková, Miroslava,Hirková, Simona,Gonda, Jozef,Pilátová, Martina Bago,G?nciová, Gabriela
, p. 26 - 36 (2016/10/04)
The total synthesis of the anticancer agent (+)-spisulosine has been accomplished. The strategy involved a substrate-controlled aza-Claisen rearrangement to establish the erythro-configured amino-alcohol motif followed by deoxygenation to create a methyl
A new synthesis of the phytotoxic 10-membered lactone herbarumin I
Jon Paul Selvam,Rajesh,Suresh,Chanti Babu,Venkateswarlu
experimental part, p. 1115 - 1119 (2009/10/02)
Herbarumin I a phytotoxic 10-membered lactone has been synthesized from d-(-)-isoascorbic acid in 12 steps with an overall yield of 16.8%. The methodology involved in generating the stereogenic center at C-8 is a Sharpless asymmetric epoxidation, as well 1,2-asymmetric induction followed by macrolactonization via RCM.
Synthesis of imidazolo-piperidinopentoses as nagstatine analogues
Gessier, Francois,Tschamber, Theophile,Tarnus, Celine,Neuburger, Markus,Huber, Walter,Streith, Jacques
, p. 4111 - 4125 (2007/10/03)
The syntheses of the four imidazolo-piperidino-pentoses 3-6, which belong to the D-series, and of their L-enantiomers, ent-3 to ent-6, are reported. Ascorbic acid and isoascorbic acid were converted over several steps into the L-threo/ L-erythro- and the D-etythro/D-threo-configured aldotetroses, respectively, which are the key building blocks for the eight target imidazolo-pentoses cited above. Nucleophilic addition of a metallated imidazole to any one of these four aldotetroses gave the corresponding two diastereomeric adducts, intramolecular cyclisation of which provided the expected bicyclic target molecules, with some protection and deprotection steps being unavoidable prerequisites. The structures and configurations of all eight piperidinoses in Scheme 1 were determined unambiguously, by a combination of 1H/13C NMR spectroscopy, circular dichroism (CD) and [α]D values, in conjunction with single-crystal X-ray diffraction analyses of the L-arabino and D-Iyxo azasugars ent-3 and 6. Although lacking the hydroxymethylene group in the C(5) position, the overall structure of these eight stereomers strongly resembles that of the natural product nagstatine (1), a potent inhibitor of N-acetyl-β-D-glucosaminidase. As a matter of fact, after examination of the inhibitory properties of these imidazolo-piperidinoses against six commonly encountered glycosidases, we observe that the L-arabino imidazolo-sugar ent-3 is a potent inhibitor in this series, with Ki = 1 μM both with a β-glucosidase and with a β-galactosidase. The D-ribo and D-xylo stereomers 4 and 5 proved to be inhibitors of a β-glucosidase of similar magnitude (4: Ki = 20 μM; 5: Ki = 17 μM), the other stereomers being either modest to poor inhibitors, or showing no inhibition at all.
Enantioselective synthesis of ethyl 4,5,7,8,9-penta-O-acetyl-2,6- anhydro-3-deoxy-D-erythro-L-gluca-nononate: A 2-monodeoxygenated derivative of '2-keto-3-deoxy-D-glycero-D-galacto-nononic acid'
Shen, Xin,Wu, Yu-Lin,Wu, Yikang
, p. 943 - 953 (2007/10/03)
A study aimed at developing an enantioselective synthesis of the title compound 23, a 2-monodeoxy analogue of the naturally occurring (+)-2-keto-3- deoxy-D-glycero-D-galacto-2-nononic acid (KDN), is reported. From D-mannose as starting material, the chiral 1,3-diene 10, activated by a silyloxy substituent at C(2), was prepared in six steps (Scheme 1). However, the intermediates were often contaminated with varying amounts of by-products arising from overoxidation during cleavage with periodic acid. An alternative route starting from the inexpensive and readily available D-isoascorbic acid (12), though a little longer than the first, satisfactorily circumvented the purification problem and led to the desired dienes 17 in good yields (scheme 2). The [Co11(S,S)-(+)-salen]-catalyzed hetero-Diels-Alder reactions of the aforementioned dienes with ethyl glyoxylate proceeded smoothly at room temperature, giving the dihydropyrano adducts 18 in moderate yields (Scheme 3). Dihydroxylation of 18a followed by reduction of the keto function gave the desired 4,5-trans dihydroxy moiety of the KDN framework (Scheme 4, see 21). The spectroscopic data of the penta-O-acetylated 2-deoxy-KDN ethyl ester 23 were consistent with those reported for the corresponding methyl ester derived from natural KDN.
