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1.
A concise total synthesis of (+)-deoxocassine (1) and (−)-deoxoprosophylline (2) has been achieved for the first time from d-xylose. The key steps involved in these synthesis are alkyl Grignard reaction, SN2 substitution of mesylate by azide, Wittig reaction, and reductive amination. 相似文献
2.
Manju Ghosh 《Tetrahedron letters》2009,50(50):7102-1119
An enantiodivergent synthesis of both enantiomers of methylenolactocin is described through stereocontrolled addition of n-pentyl magnesium bromide to two d-mannitol-derived diastereomerically related aldehydes having an α-chiral center with a β hetero atom. 相似文献
3.
Popsavin V Benedeković G Srećo B Popsavin M Francuz J Kojić V Bogdanović G 《Organic letters》2007,9(21):4235-4238
A new divergent approach to (+)-goniofufurone (1) and 7-epi-(+)-goniofufurone (2), as well as the first total synthesis of crassalactone C (3), has been achieved starting from D-xylose. In a preliminary bioassay, all three natural products 1, 2, and 3 showed remarkable in vitro antiproliferative activities against K562, Raji, and HeLa neoplastic cell lines. 相似文献
4.
Enantiodivergent formal synthesis of (+)- and (−)-muricatacins from d-xylose has been accomplished through utilization of the latent plane of symmetry present in the starting monosaccharide. This approach was extended to the preparation of two novel (+)- and (−)-muricatacin 7-oxa analogs (2 and ent-2, respectively), which showed in vitro antitumor activity toward some human malignant cells. The analog ent-2 showed a powerful antiproliferative activity against the K562 cell line, being 36-fold more potent than the standard cytotoxic agent, doxorubicin. Compound 2, however, showed a powerful cytotoxic activity against HL-60 cells, being more than 17-fold more potent with respect to the reference compound. 相似文献
5.
Satoshi ImutaShinya Ochiai Miho KuribayashiNoritaka Chida 《Tetrahedron letters》2003,44(27):5047-5051
The total synthesis of (−)-actinobolin 2, an antipode of the natural product starting from d-glucose is described. A three-component coupling reaction of a functionalized cyclohexenone (+)-6, derived from d-glucose by way of Ferrier's carbocyclization, with vinyl cuprate and an aldehyde (R)-5 effectively constructed the carbon framework of 2 in a highly stereoselective manner. The formal synthesis of the natural enantiomer 1 from d-glucose was also achieved. 相似文献
6.
Stereoselective total synthesis of synrotolide as its diacetate from d-ribose utilizing a diastereoselective Grignard reaction, preferential (Z)-Wittig olefination, asymmetric allylation, and ring closing metathesis as key steps is reported. 相似文献
7.
A key intermediate corresponding to a rare sugar framework has been synthesized, starting from d-xylose, an inexpensive carbohydrate. This approach gave access to new elaborated sugar moieties for structure–activity relationships in the KRN research. 相似文献
8.
The total synthesis of the actin-targeting metabolite (−)-microcarpalide is described. Ring-closing metathesis of a dienic ester was used as the key step. d-Mannitol was used as the chiral pool material for the construction of the olefinic acid moiety as well as the olefinic alcohol moiety of the molecule. 相似文献
9.
A novel ten-step synthesis of (+)-oxybiotin, a biologically active analogue of (+)-biotin, has been achieved starting from d-arabinose. 相似文献
10.
The enantiopure total synthesis of (−)-codonopsinine is described from commercially available l-xylose in 20% overall yield. The key steps included Julia trans olefination and cascade epoxidation-cyclisation strategies. 相似文献
11.
A stereoselective total synthesis of ophiocerin D is reported by a combination of a ‘chiron’ approach and an asymmetric synthesis, from d-xylose. Of the four stereogenic centers, the vic diols C3/C4 and C5/C6 were obtained by Sharpless asymmetric dihydroxylation and from d-xylose, respectively. 相似文献
12.
Mohammad Abrar Alam 《Tetrahedron letters》2008,49(38):5534-5536
A total synthesis of (+)-lentiginosine, a potent and selective amyloglucosidase inhibitor, is reported from a d-glucose-derived epoxide in 38% overall yield. In this synthesis, ambient conditions and readily available starting materials and reagents are used. 相似文献
13.
The total synthesis of (+)-epiquinamide, a novel quinolizidine alkaloid isolated from the Ecuadoran poison frog, Epipedobates tricolor is described. The key step includes a ring-closing metathesis reaction to construct both the six member rings. d-Mannitol was used as a chiral pool material. 相似文献
14.
The first total synthesis of the marine natural product, (S)-clavulazine has been accomplished. d-Mannitol was used as a chiral starting material. Enantioselective zinc-mediated allylation, and ring-closing metathesis are the key steps in the synthesis. Subsequent condensation followed by dehydrogenation yielded the natural product, (S)-clavulazine. 相似文献
15.
A short and practical procedure for the preparation of C-2 substituted polyhydroxypyrrolidines is described. The C-2 substituent is introduced by a stereoselective addition of a Grignard reagent to a 2,3,5-protected aldofuranose and the cyclization to the pyrrolidine ring system is performed through a bis-mesylation/double nucleophilic displacement sequence. The efficiency of the methodology was demonstrated by its application to the synthesis of HomoDMDP and DMDP. 相似文献
16.
Stereoselective approach for the synthesis of both enantiomers of bio-active decanolactone microcarpalide is described from l-tartaric acid. The synthesis of the key intermediates en route to the natural product is achieved from l-tartaric acid involving the elaboration of γ-hydroxy amide derived from tartaric acid and ring opening of an epoxide derived from tartaric acid. 相似文献
17.
A chiron approach starting with 3-O-benzyl-1,2-O-isopropylidene-α-d-xylo-pentodialdo-1,4-furanose utilizing a Grignard reaction, Mitsunobu stereoinversion, ethyl diazoacetate addition, and selective reduction of the ketone is employed as a key step for the total synthesis of (+)-cardiobutanolide described; a similar strategy is also reported for the first total synthesis of (+)-3-epi-cardiobutanolide. 相似文献
18.
A total synthesis of d-(+)-biotin is described starting from d-(+)-glucosamine using acyliminium chemistry. 相似文献
19.
We report here a simple and convenient route for the stereoselective synthesis of (R)-(−)- and (S)-(+)-homocitric acid lactones, which play very important roles in biochemistry. The method involves only three steps, starting from the readily available methyl 3-iodopropionate and d-malic acid or l-malic acid, respectively. The stereoconfiguration of the target molecules has been achieved via a self-regeneration approach with over 98% diastereoselectivity and significantly improved yield over the previous methods. 相似文献
20.
Hiroki Tanimoto 《Tetrahedron letters》2007,48(36):6267-6270
The stereoselective total synthesis of (+)-galanthamine (+)-1 starting from d-glucose is described. The cyclohexene ring in (+)-1 was prepared in an optically active form from d-glucose using Ferrier’s carbocyclization reaction, and the critical quaternary carbon was stereoselectively generated via chirality transfer based on the Claisen rearrangement of a cyclohexenol. The dibenzofuran skeleton was effectively constructed by the bromonium ion-mediated intramolecular cyclization of a cyclohexene possessing a phenolic ether function. After the introduction of a carbon-carbon double bond, the Pictet-Spengler type cyclization, followed by the reduction of the amide function completed the chiral synthesis of (+)-1. 相似文献