85514-84-7Relevant articles and documents
2-{(4a′S,6a′S,10a′R,10b′R)-Octahydrospiro[1,3-dioxolane-2,2′-pyrano[2,3-c]chromen]-6a′(1′H)-yloxy}ethanol in the Synthesis of (2S)- and (2R)-Dodecane-1,2-diols
Faizullina, L. Kh.,Petrova, S. F.,Salikhov, Sh. M.,Tagirov, A. R.,Valeev, F. A.
, p. 1840 - 1843 (2020)
Abstract: Michael adduct of levoglucosenone and cyclohexanone, 1,6-anhydro-3,4-dideoxy-4-C-(2-oxocyclohexan-1-yl)-β-D-erythrohexo-2-ulose, was treated with ethylene glycol in the presence of oxalic acid, and the resulting mixed ketal, 2-{(4a′S,6a′S,10a′R,10b′R)-octahydrospiro[1,3-dioxolane-2,2′-pyrano[2,3-c]chromen]-6a′(1′H)-yloxy}ethanol, was used a chiral auxiliary in the synthesis of vicinal diols.
Synthesis and enantioselective transport studies of both enantiomers of new chiral proton-ionizable crown ethers containing a diarylphosphinic acid unit
Szabó-Szentjóbi, Hajnalka,Bagi, Péter,Müller, Judit,Balogh, Gy?rgy Tibor,Tóth, Tünde,Huszthy, Péter
, p. 1275 - 1281 (2019/01/30)
The synthesis of four new enantiopure crown ethers containing a diarylphosphinic acid unit has been carried out. As a continuation of our work in this field, the enantioselective transport ability of these ligands for chiral amines has been studied in an
Lipase-catalyzed stereoresolution of long-chain 1,2-alkanediols: A screening of preferable reaction conditions
Parve, Jaan,Reile, Indrek,Aid, Tiina,Kudrja?ova, Marina,Müürisepp, Aleksander-Mati,Vallikivi, Imre,Villo, Ly,Aav, Riina,Pehk, T?nis,Vares, Lauri,Parve, Omar
, p. 60 - 69 (2015/04/14)
Scalable lipase-catalytic method for the kinetic resolution of long-chain 1,2-alkanediol enantiomers via stereoselective cleavage of esters was developed. The influence of lipase, reaction medium, nucleophile, temperature and the structure of the acyl group on the reaction velocity, the stereopreference and the stereoselectivity of the deacylation was studied. In addition, the rate of the spontaneous intramolecular migration of different acyl groups was determined for the intermediate 2-monoesters. The acyl group migration may diminish the apparent stereoselectivity of the two-step process if fast migrating acyl groups are used. It was found that the migration rate of different acyl groups differs by up to two orders of magnitude, being faster for acetyl and isobutyryl and much slower for butyryl and benzoyl groups. The best results were obtained by the sequential methanolysis of bis-butyryl-1,2-alkanediols in an acetonitrile/methanol mixture catalyzed by Candida antarctica lipase B (CALB) at 20 °C, affording (S)-1,2-alkanediols. Stereo- and chemoselective crystallization of the deacylated (S)-1,2-alkanediols from the reaction mixture complements the enzymatic process improving the stereochemical purity to up to ee > 99.8%. (R)-1,2-Alkanediol 2-monoesters were separated from the mother liquor and enriched stereochemically by repeated incubation with CALB, then separated, hydrolyzed with alkali and crystallized to afford (R)-alkanediols of ee > 99.8%.
Asymmetric hydrolytic kinetic resolution with recyclable polymeric Co(iii)-salen complexes: A practical strategy in the preparation of (S)-metoprolol, (S)-toliprolol and (S)-alprenolol: Computational rationale for enantioselectivity
Roy, Tamal,Barik, Sunirmal,Kumar, Manish,Kureshy, Rukhsana I.,Ganguly, Bishwajit,Khan, Noor-Ul H.,Abdi, Sayed H. R.,Bajaj, Hari C.
, p. 3899 - 3908 (2015/02/19)
A series of chiral polymeric Co(iii)-salen complexes based on a number of achiral and chiral linkers were synthesized and their catalytic performances were assessed in the asymmetric hydrolytic kinetic resolution of terminal epoxides. The effects of the linker were judiciously studied and it was found that in the case of the chiral BINOL-based polymeric salen complex 1, there was an enrichment in catalyst reactivity and enantioselectivity of the unreacted epoxide, particularly in the case of short as well as long chain aliphatic epoxides. Good isolated yields of the unreacted epoxide (up to 46% compared to 50% theoretical yield) along with high enantioselectivity (up to 99%) were obtained in most cases using catalyst 1. Further studies showed that catalyst 1 could retain its catalytic activity for six cycles under the present reaction conditions without any significant loss in activity or enantioselectivity. To show the practical applicability of the above synthesized catalyst we have synthesised some potent chiral β-blockers in moderate yield and high enantioselectivity using complex 1. The DFT (M06-L/6-31+G??//ONIOM(B3LYP/6-31G?:STO-3G)) calculations revealed that the chiral BINOL linker influences the enantioselectivity achieved with Co(iii)-salen complexes. Further, the transition state calculations show that the R-BINOL linker with the (S,S)-Co(iii)-salen complex is energetically preferred over the corresponding S-BINOL linker with the (S,S)-Co(iii)-salen complex for the HKR of 1,2-epoxyhexane. The role of non-covalent C-H?π interactions and steric effects has been discussed to control the HKR reaction of 1,2-epoxyhexane.
Synthesis of linear aza and thio analogues of acetogenins and evaluation of their cytotoxicity
Villo, Piret,Toom, Lauri,Eriste, Elo,Vares, Lauri
, p. 6886 - 6899 (2013/11/06)
We report the stereoselective synthesis of thio and aza analogues of Annonaceous acetogenins. The synthetic route allows easy variation of the stereochemistry and of the thio- and aza-fragments. Kinetic resolution of terminal bis-epoxides was used to set two remote stereocentres with high enantio- and diastereoselectivities in one step. The cytotoxicity of the analogues was assessed using the HeLa cell line. Four aza and two thio analogues of Annonaceous acetogenins were synthesized according to a general synthetic route. Two remote stereocentres in the analogues were set with high enantio- and diastereoselectivity in one step by hydrolytic kinetic resolution of a terminal bis-epoxide. Copyright
Studies on mimicry of naturally occurring annonaceous acetogenins: Non-THF analogues leading to remarkable selective cytotoxicity against human tumor cells
Zeng, Bu-Bing,Wu, Yikang,Jiang, Sheng,Yu, Qian,Yao, Zhu-Jun,Liu, Zhong-Hai,Li, Hong-Yan,Li, Yan,Chen, Xiao-Guang,Wu, Yu-Lin
, p. 282 - 290 (2007/10/03)
A class of structurally simplified analogues of the naturally occurring annonaceous acetogenins were developed, amongst which some non-THF analogues showed remarkable cytotoxicities against tumor cell lines, as well as good selectivity between human tumor cells and normal cells. The synthetic routes were significantly shortened because of the removal of the chiral centers bearing the THF rings on the natural templates. This simplification also provides access to the parallel synthesis of these mimics by a combinatorial strategy. The remaining stereogenic centers at the positions α to the ethereal links were introduced by the Chiron approach from the easily accessible chiral building blocks 6a and/or 6b, made in turn from L-ascorbic acid or Dmannitol, while the one in the butenolide segment was taken from L-lactate. All four diastereomeric non-THF analogues 2a-2d showed remarkable activity against the HCT-8 cell line, and better differentiation was found when testing against the HT-29 cell line. It was also discovered that both the butenolide and ethylene glycol subunits play essential roles in the cytotoxicities against tumor cell lines, while the 10-substituted hydroxy group and the absolute configuration of methyl group at the butenolide moiety are less important for their activity.
Enantiopure simple analogues of annonaceous acetogenins with remarkable selective cytotoxicity towards tumor cell lines
Zeng, Bu-Bing,Wu, Yikang,Yu, Qian,Wu, Yu-Lin,Li, Yan,Chen, Xiao-Guang
, p. 1934 - 1937 (2007/10/03)
Structure simplification with conservation of the essential functionalities for biological activity has been achieved with the design and synthesis of four analogues of annonaceous acetogenins. The compounds ((15 R/S, 24 R/S)-1) are easily synthesized wit
