title: X-ray crystallography of chemical compounds.
abstract: OBJECTIVE
  Accurate knowledge of molecular structure is a prerequisite for rational drug design. This review examines the role of X-ray crystallography in providing the required structural information and advances in the field of X-ray crystallography that enhance or expand its role.
  
  
  METHODS
  X-ray crystallography of new drugs candidates and intermediates can provide valuable information of new syntheses and parameters for quantitative structure activity relationships (QSAR).
  
  
  RESULTS
  Crystallographic studies play a vital role in many disciplines including materials science, chemistry, pharmacology, and molecular biology. X-ray crystallography is the most comprehensive technique available to determine molecular structure. A requirement for the high accuracy of crystallographic structures is that a 'good crystal' must be found, and this is often the rate-limiting step. In the past three decades developments in detectors, increases in computer power, and powerful graphics capabilities have contributed to a dramatic increase in the number of materials characterized by X-ray crystallography. More recently the advent of high-throughput crystallization techniques has enhanced our ability to produce that one good crystal required for crystallographic analysis.
  
  
  CONCLUSIONS
  Continuing advances in all phases of a crystallographic study have expanded the ranges of samples which can be analyzes by X-ray crystallography to include larger molecules, smaller or weakly diffracting crystals, and twinned crystals.
authors.affiliation: Naval Research Laboratory, Code 6030, 4555 Overlook Ave., Washington, DC 20375, United States. deschamps@nrl.navy.mil
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Deschamps
mesh_terms: D002626:Chemistry, Pharmaceutical / Q000379:methods; D003460:Crystallization; D018360:Crystallography, X-Ray / Q000379:methods*; D015195:Drug Design; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D021281:Quantitative Structure-Activity Relationship; D013678:Technology, Pharmaceutical / Q000379:methods
chemical_list: D004364:Pharmaceutical Preparations