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排序方式: 共有62条查询结果,搜索用时 14 毫秒
1.
ValeryN. Kalinin IgorV. Shishkov SergeyK. Moiseev ElviraE. Shults GenrikhA. Tolstikov NataliaI. Sosnina PavelV. Petrovskii KonstantinA. Lyssenko Helmut Schmidhammer 《Helvetica chimica acta》2006,89(5):861-869
In a search for starting materials for the preparation of 7,8‐fused morphine alkaloid derivatives, 8‐[(1E‐2‐phenylethenyl]codeinone dimethyl ketal ( 4 ) and 8‐[(1E‐2‐phenylethenyl]codeine ( 5 ) were prepared. These dienes were used as substrates in the Diels–Alder reactions. Compound 5 formed the ‘normal’ adduct 12 with N‐phenylmaleimide, while compound 4 behaved in reactions with dienophiles as the ‘masked’ diene 11 , a 8‐[(1E)‐2‐phenylethenyl]‐substituted thebaine, yielding the corresponding 19‐substituted 6,14‐endo‐etheno‐6,7,8,14‐tetrahydrothebaines. Specifically, reaction of 4 with methyl vinyl ketone gave rise to 19‐[(1E)‐phenylethenyl]thevinone ( 14 ) whose structure was elucidated by an X‐ray diffraction analysis. The thebaine derivative 11 was also prepared from 4 . 相似文献
2.
Versatile fluorescence probes of protein kinase activity 总被引:1,自引:0,他引:1
We introduce a versatile fluorescent peptide reporter of protein kinase activity. The probe can be modified to target a desired kinase by changing the kinase recognition motif in the peptide sequence. The reporter motif contains the Sox amino acid, which generates a fluorescence signal when bound to Mg2+ present in the reaction mixture. The phosphorylated peptide exhibits a much greater affinity for Mg2+ than its unphosphorylated analogue and, thus, a greater fluorescence intensity. Product formation during phosphorylation by the kinase is easily followed by the increase in fluorescence intensity over time. These probes exhibit a 3-5-fold increase in fluorescence intensity upon phosphorylation, the magnitude of which depends on the substrate. Peptides containing the reporter functionality are phosphorylated on serine by Protein Kinase C and cAMP-dependent protein kinase and are shown to be good substrates for these enzymes. The principle of this design extends to peptides phosphorylated on threonine and tyrosine. 相似文献
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S. A. Osadchii E. Yu. Yakovleva M. M. Shakirov E. E. Shults G. A. Tolstikov 《Russian Chemical Bulletin》1999,48(4):796-800
A number of known allied diterpene alkaloids were isolated fromDelphinium retropilosum Sambuk, a species growing in the Altai Territory. The main one was methyllycaconitine, possessing valuable pharmacological
properties.
For Part 1, see Ref. 1.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 800–804, April, 1999. 相似文献
8.
S. A. Osadchii N. A. Pankrushina M. M. Shakirov E. E. Shults G. A. Tolstikov 《Russian Chemical Bulletin》2000,49(3):557-562
A method forN-deethylation of diterpene alkaloids of the aconitane type by the Cope reaction was developed using conversions of lappaconitine and elatine as examples. The previously unknown nitrones ofN-deethylated lappaconitine, elatine, and elatidine were prepared. 相似文献
9.
Sergey S. Patrushev Tatyana V. Rybalova Igor D. Ivanov Valentin A. Vavilin Elvira E. Shults 《Tetrahedron》2017,73(19):2717-2726
The eudesmane-type methylene lactones (isoalantolactone, alantolactone, 4,15-epoxyisoalantolactone, 2′,2′-dichloro-4H-spiro[cyclopropane-1′,4-eudesma-11(13)-en-8β,12-olide], and alantolactone) react with 8-bromoxanthines (8-bromocaffeine, 8-bromotheobromine, 8-bromo-3-butyltheobromine, 8-bromotheophylline, 8-bromo-9-butyltheophylline) under Heck reaction conditions to produce the target (E)-13-(2,6-dioxo-2,3-dihydro-1H-purin-8-yl)eudesma-4(15),11(13)-dien-8β,12-olides and the subsequent endocyclic isomers - 11-(2,6-dioxo-2,3-dihydro-1H-purin-8-yl)-13-normethyleudecma-4(15)-7(11)-dien-8α,12-olides. It was revealed that the yield and product ratio depends on the reaction conditions and the structure of methylene lactone. The effectiveness of Pd(OAc)2–caffeine catalytic system has been demonstrated in this reaction. The electric eel acetylcholinesterase inhibitory activity of the eudecmanolide-xanthine hybrids was evaluated. Among the new type bisheterocycles compound 27 with butyl and 2-oxodecahydronaphtho[2,3-b]furan-3(2H)-ylidene)methyl substituents at C-7 and C-8 of the xanthine core showed moderate activity with IC50 value of 40 μM. 相似文献
10.
E. E. Shults S. P. Bondarenko M. M. Shakirov I. Yu. Bagryanskaya G. A. Tolstikov 《Russian Journal of Organic Chemistry》2010,46(11):1709-1718
Methods of synthesis were developed for 7-(furan-2-yl)-substituted 7,8,10,10a-tetrahydrobenzo[c] chromen-6,9-diones by regioselective [4+2]-cycloaddition of coumarin-3-carboxylic acids to 2-(3-trimethylsiloxybuta- 1,3-dien-1-yl)furans.
The [4+2]-cycloaddition was efficiently catalyzed with L-proline. 相似文献