Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.mce.biophys.msu.ru/archive/doc15435/doc.pdf Дата изменения: Wed Sep 26 16:04:04 2007 Дата индексирования: Mon Oct 1 20:06:38 2012 Кодировка: IBM-866

O=C-N-H Lн . ., . ., . ., . .

(, )
MP2 3 - O=C-N-H Lн. . . . . , -, , лЁ. , , , -- =-N-H -- , [1], [2н4]. , , . 455


7. , Part 7. Mathematical Models In Biology, Ecology And Chemistry

O=C-N-H Lн. . - HF, MP2- ( , 6н311++G**) 3- . (, , , , , ) 20 l-. O=C-N-H . . . лЁ . : ) (. 1 ) [5]; ) - - (. 1 ) [6]; ) , лЁ (. 1 ) [2,3].

456


. . . -- -- 2006, . 2, . 444н454 Samchenko A. A. at al -- MCE -- 2006, v. 2, p. 455н466






. 1.

O=C-N-H . [Biopolymers. 1968, 6, 1494н1496] , , . (sp3) . , , ( н ) , , , . [7,8], , -NH2 . sp3- sp2- 457


7. , Part 7. Mathematical Models In Biology, Ecology And Chemistry

. / [9,10], [10,11].

, ~ 1 -

. 2. , NH2 ( -- [R.D.Brawn et al 1987, J.Mol. Spectrsc.]; -- ab initio MP2/6-31G* [K.B.Wiberg, P.R.Rablen, 1995, J.Am.Chem.Soc.]; -- 3 [ ]; -- MP2/6-311G** [ ])

[7,12,13] - =-N-H нн . (), : н. [14]. , , . , , - 458


. . . -- -- 2006, . 2, . 444н454 Samchenko A. A. at al -- MCE -- 2006, v. 2, p. 455н466

. 2 NH2- =-N . , , , лЁ . 3- N-H . н400 +400 NH . ab initio MP2/6-31G* , , . . , , 3- . 3- . , , , , , . , [7,9,11] [7,9н11,15], 459


7. , Part 7. Mathematical Models In Biology, Ecology And Chemistry

N-H (N-R) . , , ( 3).

. 3. 3- , H2C=CH-NH2,

N- н , , 0,2 / O=C-N-H N-H(R) . . - . ,

460


. . . -- -- 2006, . 2, . 444н454 Samchenko A. A. at al -- MCE -- 2006, v. 2, p. 455н466

. 3- , , , ab initio , , . 4, , MP2 N- .

. 4. 2 N- ( O=C-N)

-

461


7. , Part 7. Mathematical Models In Biology, Ecology And Chemistry

. sp3- . , O=C-N-H . ( N-H ~ 200) sp3- N.

1. 3- N-H =-N ( -- N-H , -- N-H )

. , 3-, 2 , - =-N-. , .. -

462


. . . -- -- 2006, . 2, . 444н454 Samchenko A. A. at al -- MCE -- 2006, v. 2, p. 455н466

. 1 20 L-. , =-N-H . лЁ лЁ ( ) . N-H , лЁ N-H , , ( -) ( -) .

. 4. 3- - 7

, , , - , 7 -

463


7. , Part 7. Mathematical Models In Biology, Ecology And Chemistry

. 4. , , 3- 7- . , -. , -. . O=C-N-H -. - - . . , . . 1. , , , O=C-N-H , . 2. O=C-N-H . 3. - - .


1. Pauling, L., Corey, R.B., Branson, H.R. The structure of proteins: two hydrogen-bonded helical configurations of the polypeptide chain. // Proc.N.A.S. -- 1951. -- V. 37. -- P. 205н211. 2. MacArthur, M. W.; Thornton, J.M. Deviations from planarity of the peptide bond in peptides and proteins. // J.Mol.Biol. -- 1996. -- V. 264. -- P. 1180. 3. Carugo, O Incoherent relationship between torsion values and bonds

464


. . . -- -- 2006, . 2, . 444н454 Samchenko A. A. at al -- MCE -- 2006, v. 2, p. 455н466

4.

5. 6.

7. 8.

9. 10.

11. 12.

13.

14.

15. 16.

lengths in atomic resolution protein crystal structures. // Acta. Chim. Slov. -- 2003. -- V. 50. -- P. 505. Sulzbach, H. M.; Schleyer, P.v.R.; Schaefer,III H.F. Influence of the nonplanarity of the amide moiety on computed chemical shifts in peptide analogs. Is the amide nitrogen pyramidal? // J.Am.Chem.Soc. -- 1995. -- V.117. -- P. 2632н2637. AlanG.Walton Polipeptides and protein structure. н Elsevier NewYork, 1981. -- 393 c. Zagrovic, B.; Jayachandran, G.; Ian S. Millett, Doniach, S.; Vijay S. Pande, V.S. How Large is an -Helix? Studies of the Radii of Gyration of Helical Peptides by Small-angle X-ray Scattering and Molecular Dynamics.// J.Mol.Biol. -- 2005. -- V.353. -- P.232н241 Brown, R.D.; Godfrey, P.D.; Kleibmer, B. The inversion-torsion motion in vinylamine. // J.mol.spectroscopy 1987. -- V. 124. -- P. 21 V.M.Komarov, R.V.Polozov, G.G.Konoplev Non-planar structure of nitrous bases and non-coplanarity of Watson-Crick pairs. // J.theor. Biol.1992. -- V.155. -- P.281н294. Wong, M. W.; Wiberg, K.B. Structure of acetamide: planar or nonplanar? // J.Phys.Chem. -- 1992. -- V.96. -- P.668н671. Jean, Y.; Demachy, I.; Lledos, A.; Maseras, F. Electronic agaist steric effects in distorted amides. // J.Mol.Struct.(THEOCHEM) 2003. -- V.632. -- P.131н144. Mack, H.-G.; Oberhammer, H. Planarity of N, N-dimetylacetamide, (CH3)2NC(O)CH3. // J.Am.Chem.Soc. -- 1997. -- 119. 567. K.Ohba, T.Usami, Y.Kawashima, E.Hirota Fourier transform microwave spectra and ab initio calculation of N-ethylformamide // J.Mol.Strc. 2005. -- V.744н747. -- P.815н819. .., .., .. . PCILO . // . . , 1989. .. - . PCILO . I. - - . // . .39, .5, 1994. Brown, R.D., Godfrey, P.D., Kleibomer, B. The conformation of formamide. J.Mol.Spectroscopy 1987, 124, 34н45. NoemiG.Mirkin, S.Krimm Structure of trans-N-methylacetamide: planar or non-planar symmetry? // J.Mol.Stuct (Theochem) 1995. V.334. P.1н6.

465


7. , Part 7. Mathematical Models In Biology, Ecology And Chemistry

ON THE NON-PLANATRITY OF O=C-N-H GROUP IN SINGLE AMIDES AND DIPEPTIDES OF L-AMINOACIDS Samchenko A. A., Kondratiev M. S., Kabanov A. V., Komarov V. M.

(Russia, Pushchino)

By using ab initio MP2 and semi-empirical 3 quantum-chemical calculations we discussed the non-planar structure bistability of O=C-N-H fragment in the form organization of simple amides and dipeptides. Influence of chemical substitution on structural polymorphism of the peptide group is shown.

466