Drug, development

The partition coefficient and aqueous solubility are properties important for the study of the adsorption, distribution, metabolism, excretion, and toxicity (ADME-Tox) of drugs. The prediction of the ADME-Tox properties of drug candidates has recently attracted much interest because these properties account for the failure of about 60 % of all drug candidates in the clinical phases. The prediction of these properties in an early phase of the drug development process could therefore lead to significant savings in research and development costs. 

The metabolism ofa potential drug has to be considered at an early phase of the drug development process. 

In particular, in silico methods are expected to speed up the drug discovery process, to provide a quicker and cheaper alternative to in vitro tests, and to reduce the number of compounds with unfavorable pharmacological properties at an early stage of drug development. Bad ADMET profiles are a reason for attrition of new drug candidates during the development process [9, 10]. The major reasons for attrition of new drugs are ... 

Lead structure According to Valler and Green s definition a lead structure is a representative of a compound series with sufficient potential (as measured by potency, selectivity, pharmacokinetics, physicochemical properties, absence of toxicity and novelty) to progress to a full drug development program [12]. 

M. Mathieu, New Drug Development A. Begulatory Overview, Parexel, Waltham, Mass., 1994. 

T. R. Sweeney, M Survey of Compoundsfrom the Hntiradiation Drug Development Program of the U.S. Army Medical Research and Development Command Walter Reed Army Institute of Research, Washington, D.C., 1979. 

N. Ikekawa, in H. Danielsson and. Sjovah, eds.. Steroids andBile Acids, Elsevier Science Pubhshers BV, Amsterdam, the Nethedands, 1985, pp. 199—230 C. Djerassi, in P. Krogsgaard-Larsen, S. Brogger Christensen, and H. Kofod, eds., Alfred Benpon Symposium 20 Natural Products and Drug Development, Munksgaard, Copenhagen, Denmark, 1984, pp. 164—176 N. W. Withers, in P. J. Scheuer, ed.. Marine Natural Products, Vol. V, Academic Press, Inc., New York, 1983, pp. 87—130 C. Djerassi, Pure Appl Chem. 53, 873 (1981). 

To extract the conformational properties of the molecule that is being studied, the conformational ensemble that was sampled and optimized must be analyzed. The analysis may focus on global properties, attempting to characterize features such as overall flexibility or to identify common trends in the conformation set. Alternatively, it may be used to identify a smaller subset of characteristic low energy conformations, which may be used to direct future drug development efforts. It should be stressed that the different conformational analysis tools can be applied to any collection of molecular conformations. These... 

It will be interesting to see how much of this activity will survive in post-war conditions, especially in competition with new, synthetic, anti-malarial drugs developed during the war and revival of the Java cinchona industry, which is apparently making progress. 

For the past few years, however, there has been a hiatus in the pace of discovery of novel medicinal agents. It has been postulated by some that the field has now slowed down due to the limitations of the almost strictly empirical approach that has been applied to date to drug development. It is possible, too, that the higher standards of efficacy and safety that a new drug must meet today, combined with the enormously increased costs of clinical trials, have acted to keep all but the most promising new drugs off the market. 

Tlie previous chapter traced the evolution of a biologically ac-I ive compound isolated from plant material—cocaine—into an extensive series of drugs by chemical dissection of that molecule. A-iiother frequently applied approach to drug development depends on I ho identification and study of the organic compounds that regu-l. ite most of the functions of mammalian organisms the hormones,... 

The total syntheses of penicillin and cephalosporin represent elegant tours de force that demonstrated once again the power of synthetic organic chemistry. These syntheses, however, had little effect on the course of drug development in the respective fields, since they failed to provide access to analogs that could not be prepared by modification of either the side chains or, as in the case of more recent work, modification of 6-APA and 7-ACA themselves. In order to have an impact on drug development, a total synthesis must provide means for preparing... 

The line of reasoning that leads from morphine to the 4-phenyl-piperidines is so clear—if unhistoric—as to demand exposition in an integral chapter. The chronologically oriented chapter on the development of the local anesthetics is included specifically to give the reader some appreciation of one of the first approaches to drug development. 

Abdoul-Enein, H. Y Wainer, I. W. The Impact of Stereochemistry on Drug Development and Use Wiley-VCH New York, 1997. 

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