[Three dimensional quantitative structure-activity relationship of heterocyclic-compounds with di-tert-bultylphenyl inhibitors].

AIM: To quatitatively disclose the relationship between activity and structure of a new class of COX-II inhibitors containing dialkylphenyl-linked heterocyclic moieties. METHODS AND RESULTS: Seventeen COX-II inhibitors from literature as a training set were investigated with the aim of developing a 3D-QSAR model using comparative molecular field analysis (CoMFA). To reveal the pharmacophoric pattern, several modes of superimposition were explored. The significant model shows a higher ability to explain and predict the activity of COX-II inhibitors, with the cross-validation RCV2 = 0.718, non cross-validation R2 = 0.992, F = 260,624, and SEE (standard error of estimate) = 0.072. Three compounds were selected as a predicting set, the low deviations of calculated values from the measured ones suggesting a powerful predictive ability of the model. CONCLUSION: The 3D-QSAR explains the dependence of COX-2 inhibition upon the structures of the compounds. Some structure information for design of new COX-II inhibitors with higher activity has been given.

[Studies on antipeptic ulcer agents: the synthesis and QSAR analysis of heterocycle aldehyde N4-substituted phenyl(thio)semicarbazones].

Forty-five condensation products of furan-, pyrrole-, and N-methyl pyrrole-alpha-carboaldehyde with N4-3-or 4-substituted phenyl semicarbazides and thiosemicarbazides were designed and synthesized to optimize the antiulcer activity. Quantitative structure-activity relationships reveal that in the series of semicarbazones increase in hydrophobicity of molecules and introduction of electron-repelling groups onto the phenyl ring raise the antiulcer activity; Generally, the activity of semicarbazones is higher than that of the corresponding thiosemicarbazones. The large spans between activity and toxicity of compounds No. 17 and 30 led to further investigation of pharmacological actions.

[Studies on antipeptic ulcer agents: the synthesis and structure-activity relationship analysis of heterocycle aldehyde (thio) semicarbazones and acyl hydrazones].

Twenty-eight condensation products of heterocycle-alpha-carboaldehydes with N-aminooxazolidones, semicarbazides, thiosemicarbazides, aminoguanidines, aromatic hydrazides and benzoxycarbonyl hydrazide were synthesized so as to deduce the antiulcer pharmacophore or fragment of furazolidone(I), the prototype, which shows therapeutic efficacy for patients with gastric ulcer. Analysis of the SAR of the compounds indicate that the substitution of furan, thiophene, pyrrole and N-methyl pyrrole rings for the 5-nitrofuran and the cleavage of the oxazolidone ring obtain the activity to some extent. The necessary electronic density of carbonyl group of compounds is of importance. A lead structure, therefore, is derived for further optimization.

[Synthesis of triphenylethylene with aliphatic cyclic moiety and its antagonism on estrogen receptor].

AIM: In order to improve the biological activity and reduce the side effects and toxicity, a series of novel estrogen receptor antagonists were designed. METHODS: The key triphenylethylene intermediates were obtained by the McMurry reaction. The target compounds were prepared by etherification. The binding affinities of the target compounds for the estrogen receptor in rat uterine cytosol were measured by a competitive binding assay and their estrogen agonistic/antagonistic properties were investigated in the 3-day uterine weight assay in the immature rats. RESULTS: Thirty-five new compounds have been synthesized and their geometric configuration were determined by X-ray crystallography and 1HNMR spectral data. CONCLUSION: All of the test compounds showed affinity for the estrogen receptor (IC50 < 10(-6) mol.L-1), especially compound 35 with IC50 1.07 x 10(-8) mol.L-1. Some compounds are antagonists, inhibiting uterus growth; others are agonists, promoting uterus growth. Compounds 14 and 27 are superior antagonists to tamoxifen.

[Studies on retinoids. IV. Design, synthesis and structure-activity relationships of di-t-butylphenyl compounds].

Retinoic acid and its analogues play important roles in modulating cell growth, differentiation, immunity and apoptosis. Clinically they are used for cancer chemoprevention and chemotherapy. Based upon the moiety of 3,5-di-t-butyl-4-hydroxy phenyl ring, a series of substituted aromatic amide, ester and chalcones were designed and synthesized, which mimic the molecular shape, size, and spacial disposition of functional groups of retinoic acid. The general structure is as follows: [formula: see text] where R stands for hydrogen atom or methyl group, Y is the linkage -CONH-, -NHCO-, -COO-, -COCH = CH-, or a member of a heterocycle, X represents various substituents at different positions. The SAR indicates that the presence of hydrophobic group(s) at one end of the molecule, and a carboxyl group at the other end, and a conjugative system of molecule are necessary and full prerequisite for exhibiting activity. Loss of any one factor of them will abolish the activity. Being obligatory for anti-oxidative effect, the phenolic hydroxy group does not convey biological activity, because after methylation of the hydroxy group the compound increases the differentiation-inducing activity and loses the anti-oxidative effect, indicating that there is no correlation between the two activities. With a stable conformation of two phenyl rings with cis-conformation N-methylated acyl amide (No. 30) features in bent shape of the molecule, instead of an extended conformer, which is taken by the non-N-methylated partner and all-trans retinoic acid. A bent conformer of No. 30 accounts for the inactivity. In this paper compounds No. 4f, 4g, 5a, 7, 13, 32, 37, and 38 exhibited significant activity among them 4-[3-(3, 5-di-t-4-methoxyphenyl)-3-oxo-1-propenyl] benzoic acid (No. 38) showed high activity comparable to that of retinoic acid. The pharmacological action of No. 38 is under investigation.