Reference

CoMFA Modeling of Human Catechol O-Methyltransferase Enzyme Kinetics

CoMFA Modeling of Human Catechol O-Methyltransferase Enzyme Kinetics. Sipilae, Julius; Taskinen, Jyrki (Division of Pharmaceutical Chemistry, Department of Pharmacy, University of Helsinki, Helsinki 00014, Finland). Journal of Chemical Information and Computer Sciences, 44(1), 97-104 (English) 2004 American Chemical Society. CODEN: JCISD8. ISSN: 0095-2338. DOCUMENT TYPE: Journal CA Section: 7 (Enzymes) Three-dimensional QSAR models with different charge calcn. (MOPAC-AM1-ESP, MOPAC-AM1-Coulson and Gasteiger-Huckel) were developed for predicting all three enzyme kinetic parameters Km, Vmax and Vmax/Km for catecholic substrates of human sol. catechol O-methyltransferase (S-COMT). The empirical parameters of 45 substrates were correlated to the steric and electronic mol. fields of the substrates utilizing Comparative Mol. Field Anal. (CoMFA).Several substances with their cas registry numbers 99-24-1 and 123039-93-0 may be metioned in this study. Alignment rules for CoMFA were developed based on the catalytic mechanism and crystal structure of S-COMT, and the anal. was optimized using an all-space search technique. Leave-one-out and leave-n-out cross-validation (with 5 and 10 cross-validation groups) was carried out, and all developed models proved to be statistically significant with Q2 values up to 0.84. The models based on MOPAC charge calcns. predicted the empirical values clearly better than the Gasteiger-Huckel method. The derived CoMFA coeff. contour maps of steric and electrostatic interactions correlated clearly with the S-COMT crystallog. structures. .

Isolation of methyl gallate as the antitumor principle of Acer saccharinum

Isolation of methyl gallate as the antitumor principle of Acer saccharinum. Bailey, Arthur E.; Asplund, R.Several substances are used for example 9068-38-6 and 99-24-1 which are their cas registry numbers. Owen; Ali, M. S. (Dep. Chem., Univ. Wyoming, Laramie, WY 82071, USA). J. Nat. Prod., 49(6), 1149-50 (English) 1986. CODEN: JNPRDF. ISSN: 0163-3864. DOCUMENT TYPE: Journal CA Section: 11 (Plant Biochemistry) Section cross-reference(s): 1 Me gallate (I) was isolated from green leaves of A. saccharinum and identified on the basis of phys. and spectral properties. ID50 values (the concn. of I required to suppress cell growth to 50% of the control) were 4.0 ′ 10-5M for B16 melanoma of mice, 2.2 ′ 10-5M for L1210, and 2.8 ′ 10-5M for P388. At 4.80 ′ 10-3M, I inhibited reverse transcriptase by 50%. I (10-3M) had no effect on normal human fibroid cells. .