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61.
In this communication, we provide theoretical evidence that the folded structure of a simple peptide, alanine zwitterionic octapeptide, or A8, unstable in solution, becomes stable in a reverse micelle (RM) of appropriate size. Our molecular dynamics simulations were carried out for realistic models of sodium 2-ethylhexylsulfosuccinate RM in isooctane, simulated for an extended period of time. For the RM of the smaller size, we find that a helical structure is stable for the whole length of the simulation. On the contrary, the peptide very quickly takes an extended structure in larger micelles. 相似文献
62.
[Structure: see text] A practical one-pot, regiospecific three-component process for the synthesis of 2,3-disubstituted indoles was developed via consecutive Pd-catalyzed Sonogashira coupling, amidopalladation, and reductive elimination. 相似文献
63.
[Structure: see text] 2-morpholin-4-yl-4-oxo-4H-chromen-8-yl 2,2,2-trifluoromethanesulfonate is a key intermediate for the synthesis of the DNA-dependent protein kinase (DNA-PK) inhibitor 8-dibenzothiophen-4-yl-2-morpholin-4-yl-chromen-4-one (NU7441). Two improved methods for the synthesis of this triflate have been developed: (A) in 35% overall yield, through modification of the published route, and (B) in 15% overall yield, by a new route employing a Baker-Venkataraman rearrangement to enable generation of the chromenone scaffold. Both syntheses depend on the judicious use of allyl protecting groups. 相似文献
64.
Paul C. Pasles Wladimir de Azevedo Pribitkin 《Proceedings of the American Mathematical Society》2001,129(11):3177-3184
The Lipschitz formula is extended to a two-variable form. While the theorem itself is of independent interest, we justify its existence further by indicating several applications in the theory of modular forms.
65.
<正>Eudistalbin A was isolated from marine tunicate eudistoma album and possess cytotoxic activity(ED_(50)3.2μg/mL) in vitro against the growth of KB human buccal carinoma cells.The synthetic eudistalbin A showed potent inhibitory activity against the breast carcinoma cell line MDA-231 with an IC_(50) value of 2.1μmol/L using the metabolic assay MTT.All structures of new compounds were confirmed by ~1H NMR,~(13)C NMR,HRMS and optical rotation. 相似文献
66.
Let be a discrete subgroup of SL(2,
) with a fundamental region of finite hyperbolic volume. (Then, is a finitely generated Fuchsian group of the first kind.) Let
0}} {a(n)e^{2\pi i(n + {\kappa })z/{\lambda }} } ,{ }z \in \mathcal{H}.$$
" align="middle" border="0">
be a nontrivial cusp form, with multiplier system, with respect to . Responding to a question of Geoffrey Mason, the authors present simple proofs of the following two results, under natural restrictions upon .
Theorem.
If the coefficients a(n) are real for all n, then the sequence {a(n)} has infinitely many changes of sign.
Theorem.
Either the sequence {Re a(n)} has infinitely many sign changes or Re a(n) = 0 for all n. The same holds for the sequence {Im a(n)}. 相似文献
67.
Tai Sheng LU Yang Hua YI* Shi Long MAO Da Zheng ZHOU Qiang Zhi XU Hai Feng TANG Shu Yu ZHANG Center of Marine Drug Research School of Pharmacy Second Military Medical University Shanghai 《中国化学快报》2001,(8)
Cassia siamea Lam. (CSL) is a common tree in the southern part of China. It has been used as folk medicine for aperient, antiarthritic and swellings1. We report here the isolation and structural elucidation of a new chromone glucoside, 2-methyl-5-propyl-7, 12-dihydroxy chromone-12-O-(-D-glucopyranoside (1), from the n-butanol-soluble fraction of CSL extract . 1The 80% ethanolic extract of CSL was dissolved in water and partitioned with petroleum ether, dichloromethane and n-butanol. The … 相似文献
68.
N. v. Klobukow L. F. Nilson Otto Pettersson Gerhard Krüss J. Meunier W. La Coste C. Schall Gibson Dyson W. Bott D. S. Macnair Hans Malfatti Paul Schoop N. Menschutkin D. Konowalow Victor Meyer G. G. Pond Wladimir Alexeew V. Meyer T. P. Bruce Warren und W. Jäger 《Fresenius' Journal of Analytical Chemistry》1888,27(1):194-203
Ohne Zusammenfassung 相似文献
69.
Wladimir Lewicki 《Monatshefte für Mathematik》1903,14(1):96-104
Ohne Zusammenfassung 相似文献
70.