In search of new ALS inhibitors without the previous knowledge of receptor crystal structure, DISCO module was appfied to produce 3D-pharmacophore models, which provided information to design novel molecules by 3D-datahase searching. Then a number of molecules were synthesized. Several of them have some ALS inhibitory activities.

A new strategy was devised to stereo-speclfically introduce various building blocks, mainly heterocydes such as pyri-midines and trlnzlnes onto a multi-hydroxy molecule. A glu-copyranoside was chosen as a target scaffold. Two polymer-based protective reagents were jointly integrated in the imple-mentation of the strategy. It was found that in the a-D-glu-copyranoside, which has four free hydroxyl groups within the same molecule, its 4, 6-di-OH could be simultaneously pro-tected by polystyryl boronie acid, which left the 2, 3-di-OH free for substitution. Due to the steric effects within the molecule, the 2-OH is much more liabile to electrophilic stub-stitutlon. Thus the first and the second building blocks could be introduced regioselectlvely onto the 2-OH and the 3-OH positions. After a facile deprotectlon, the 4,6-di-OH were left free and by application of a second protecting reagent-polystyryltrityichlorlde onto 6-OH, a third building block was introduced onto the 4-OH position. After further deprotec-tion, the fourth building block was later introduced onto the 6-OH position. The new strategy was successfully applied in the combinatorial synthetds by application of the split-mix technique. The respective eleven small Ebraries were obtained and confirmed by I-IPI_~MS and NMR. Some preliminary results on chemical structure/herbicidal activity relationship were discussed.

用比较分子力场分析（CoM FA）方法和比较分子相似性指数分析（CoM S IA）方法研究了21个2（1H）-喹啉-2, 4-二酮类化合物抗小麦锈病的三维定量构效关系（3D2Q SAR），发现用CoM FA方法可以找到最佳的3D-Q SAR模型，并通过量子化学从头计算的方法研究了不同活性化合物的前线轨道及静电势分布图的差异。所得构效关系模型为发现更高活性的化合物提供理论指导。

Some series of 2-alkyl (alkythio)-5-((4-chloro)-3-ethyl-1-methyl-1H-pyrazole-5-yl)-1,3,4-oxadiazoles (thiadiazoles) were prepared as potential fungicides. Their fungicidal activity was evaluated against rice sheath blight, which is a major disease of rice in China. Structure-activity relationships for the screened compounds were evaluated and discussed. It was found that 5-(4-chloro-3-ethyl-1-methyl-1H-pyrazole-5-yl)-1,3,4-thiadiazole-2-thione has the higher fungicidal activity.

3-(p-methyl)anilinomethylidene-6-aryl-5,6-2H-dihydropyran-2,4-dione was selected as the model reactant compound to study the catalytic hydrogenation of 3-anilinomethylidene-6-aryl-5,6-2H-dihydropyran-2,4-diones by the AM1 semi-empirical method. Molecular information such as net charges, bond orders, values of frontier orbital energies, composition, proportions and bonding contribution was acquired and analyzed. Thus, possible reactive sites were proposed and the reaction mechanism was postulated via two different pathways. The postulated intermediates and products were also computed using the AM1 method. Their heat of formation values and energies of HOMO/LUMO/SOMO indicate that the mechanism of catalytic hydrogenation of 3-anilinomethylidene-6-aryl-5,6-2H-dihydropyran-2,4-diones is hydrogenolytic cleavage on a dihydropyrandione ring, not the simple addition of a CyC double bond. Therefore, the experiment result is elucidated theoretically.