Databases catalyst design

In proportion to the importance of the catalyst materials, experimental information on their synthesis, characterization and catalytic properties are accumulating over the years. Databases of such information could be generated and further expert system approach can be applied to optimally utilize this information for the catalyst design. Relations between the observations and inferences are expressed as mathematical expressions. These independent and interdependent mathematical expressions which relate observations to the inferences are used in the decision-making steps for predictions. Finally the recent achievements in the human interfacing technology with computers - for e g., one can talk to the molecules simulated in computer, command their motions just by waving his hands, etc. have to be seen to be believed. 

The performance of a catalyst is determined by its lifetime, activity and selectivity in converting raw materials into end products. Therefore, the design objectives are to satisfy the requested parameters for these properties. From the computational chemistry point of view, there are several different approaches in the research of catalyst design applic ion of databases and expert systems, chemistry of the catalytic process, in the nonmolecular field, and the many aspects of molecular science. 

Kurogi, Y. and Guner, O.F. Pharmacophore modeling and three-dimensional database searching for dmg design using catalyst. Curr. 

Using a transition state model for enolate formation and a database search, a thiourea with a pendant amine has been designed as a catalyst, and its ability to hydrogen bond the enolate of acetone explored.287 Both in-plane and out-of-plane hydrogen bonds, to a lone a pair and the carbonyl 7r-bond, respectively, were considered. 

Sheridan RP, Nachbar RB, Bush BL (1994) Extending the trend vector The trend matrix and sample-based partial least squares. J Comp Aided Mol Des 8 323-340 Sprague PW (1995) Automated chemical hypothesis generation and database searching with CATALYST. Persp Drug Disc Design 3 1-20... 

Sprague, P.W. (1995) Automated chemical hypothesis generation and database searching with catalyst. Perspectives in Drug Discovery and Design, 3, 1-20. 

A recent successful application of these methods was the work at Roche on DNA gyrase [146]. The LUDI maps for this site are shown in Fig. 4.6. Pharmacophores derived from these maps were used to search the corporate database using LUDI and Catalyst. Structures were deliberately chosen to be of low molecular weight and were screened at high concentration, so-called needle screening. The subsequent actives were then further developed via structure-based design techniques and medicinal chemistry to give several different series of active compounds. 

Computerizing the information on zeolite catalysts have been attempted successfully and different databases concentrate on specific properties[25-28]. The information in several databases are shown in Table 3. Our approach[29] involves retrieval of information from the database and additionally an expert system approach is followed to derive a set of conditions to achieve one s goal in the synthesis of zeolites. The structure of the system is designed to perform three salient fiinctions as shown in Fig. 7. The first function is to provide access to a large database of physico-chemical properties and crystallographic information of all reported zeolite[30]. The second function provides for the synthesis of zeolites - the most logical route for the synthesis of a desired zeolite structure is provided. The third function is a graphic tool application to simulate X-ray powder diffraction patterns for zeolite phases with different amount and nature of purity. 

There are also reports in the literature where a database on Ci catalytic chemistry is developed by Ito et al[31], computer aided design of oxidation catalysis using expert system approach[32, 33] and an expert system approach for the general design of catalysts[34], Thus processing the information by computational methods proves to be a efficient approach. 

The highly precise conduction of parallelized catalyst synthesis and testing of small amounts of material in combination with computer assisted methods for designed experiments, including the development of database tools, and modelling tools represents one of the biggest growth areas in catalysis. 

---