75445-68-0Relevant academic research and scientific papers
Enantioselective Total Synthesis of (?)-Spiroxins A, C, and D
Chen, Chong-Chong,Hu, Xiangdong,Shu, Xin,Yang, Jiayi,Yu, Tao
, p. 18514 - 18518 (2021/07/20)
Spiroxins A, C, and D are metabolites that have been identified in the marine fungal strain LL-37H248. Their unique polycyclic structures and intriguing biological activities make them attractive targets for the synthetic community. Based on a scalable en
C-Glycosylation of tri-O-benzyl-2-deoxy-D-glucose: Synthesis of naphthyl-substituted 3,6-dioxabicyclo[3.2.2]nonanes
Brimble,Brenstrum
, p. 1612 - 1623 (2007/10/03)
The syntheses of naphthol 7, naphthol 8, naphthol 11 and naphthol 12 are described, starting from juglone 13. C-Glycosylation of naphthol 8 with benzyl-protected glycosyl donor 10 using trimethylsilyl trifluoromethanesulfonate and silver perchlorate or boron trifluoride-diethyl ether affords rearranged product 36 in which the glycosyl donor has undergone an unusual 1,6-hydride shift. Use of the corresponding naphthol 12 as the glycosyl acceptor under the same conditions affords the expected C-glycoside 34. Use of the naphthol 7 and naphthol 11 affords predominantly rearranged products 35 and 37 respectively, albeit in much lower yield than the reactions using the corresponding bromonaphthols. The study described herein establishes that introduction of an acetyl group to C-3, as in C-glycosylnaphthoquinone 4, as required for conversion to analogues of medermycin 1 such as 3, necessitates that the C-glycosylation step be effected before regioselective introduction of the acetyl group.
Synthesis of a 2-deoxyglucosyl analogue of medermycin
Brimble,Brenstrum
, p. 1624 - 1634 (2007/10/03)
The synthesis of a 2-deoxyglucosyl analogue 6 of the C-glycosylpyranonaphthoquinone antibiotic medermycin 1 is described. The key 3-acetyl-6-(2-deoxyglucosyl)-1,4-naphthoquinone 7 is prepared from 6-(2-deoxyglucosyl)-1,4-naphthoquinone 21, which in turn is available by C-glycosylation of naphthol 18 with glycosyl donor 12 using BF3·Et2O in acetonitrile followed by oxidative demethylation of the derived methyl ether 20. An acetyl group is then introduced at C-3 on naphthoquinone 21 by reductive monomethylation to naphthol 22, ortho bromination to bromide 24, methylation to 9, followed by Stille coupling with α-ethoxyvinyltributyltin (and hydrolysis) to afford the 3-acetylnaphthalene 8. Addition of 2-(trimethylsilyloxy)furan 13 to naphthoquinone 7, formed from oxidative demethylation of the naphthalene 8, affords the furofuran adducts 25 and 26 as an inseparable mixture of diastereomers. Oxidative rearrangement of this diastereomeric mixture using cerium (IV) ammonium nitrate affords the unstable diastereomeric lactols 27 and 28 also as a 1:1 inseparable mixture. Reduction of these lactols 27 and 28 with triethylsilane and BF3·Et2O at - 10 °C affords ethers 29 and 30 as a 1:1 mixture. Finally, conversion of ethers 29 and 30 to a 1:1 diastereomeric mixture of medermycin analogues 6 and 31 is achieved by treatment with boron tribromide which effects removal of the methoxy group at C-7, the benzyl ethers on the 2-deoxyglucose residue, and epimerisation at C-5.
A New Synthesis of Defucogilvocarcin M
Hart, David J.,Merriman, Gregory H.
, p. 5093 - 5096 (2007/10/02)
A convergent synthesis of the title compound is described.The synthesis revolves around a MAD-mediated coupling of oxazoline 11 and naphthoquinone ketal 16 and requires eight steps via the longest linear sequence.
Dimeric Naphthoquinones, XV. Syntheses of Diomelquinone A and its Dimer, 7,7'-Dihydroxy-8,8'-dimethoxy-3,3'-dimethyl-2,2'-bi-1,4-naphthoquinone
Laatsch, Hartmut
, p. 1847 - 1865 (2007/10/02)
Diomelquinone A (3b) and its dimer 3a are synthesized starting from 8-chloroplumbagin (4a) or juglone (2a); the ortho-quinones 7a and 11a are intermediates.
Naphthoquinone Mono- and Di-methide Lactones
Carey, John L.,Shand, Charles A.,Thomson, Ronald H.,Greenhalgh, Colin W.
, p. 1957 - 1962 (2007/10/02)
Monolactones which are derivatives of 7-hydroxynaphthopyran-2,6-dione are obtained by reaction of simple juglones with ethyl chloroformylacetate, and by condensation of mandelic acid with 2,6-dibromo-1,5-dihydroxynaphthalene.Dilactones are formed
Dimeric Naphthoquinones, IV1). - Synthesis of Biramentaceone, Mamegakinone and Rotundiquinone
Laatsch, Hartmut
, p. 1321 - 1347 (2007/10/02)
Mamegakinone (8a), biramentaceone (12a), 3,3'-bijuglone (8b), 2,2-bijuglone (12b) and their methyl ethers were prepared by oxidative coupling of substituted 4-methoxy-1-naphthols; indigoids like 24 are intermediates.Cooxidation of the isomeric dimethoxy-1
