Drug molecule

Example If a drug molecule interacts with a receptor molecule through hydrogen bonds, then yon might restrain the distance between the donor and acceptor atoms involved in the hydrogen bonds. During a molecular dynamics simulation, these atoms would slay near an ideal value, while the rest of the molecular system fully relaxes. 

An article entitled When Drug Molecules Look in the Mirror in the June 1996 is sue of the Journal of Chemi ca/fdc/cat/on (pp 481-484) describes numerous exam pies of common drugs in which the two enantiomers have different biological properties... 

The temperature of a simulation depends on your objectives. You might use high temperatures to search for additional conformations of a molecule (see Quenched Dynamics on page 78). Room temperature simulations generally provide dynamic properties of molecules such as proteins, peptides, and small drug molecules. Low temperatures (<250 K) often promote a molecule to a lower energy conformation than you could obtain by geometry optimization alone. 

Pharmacophore. The portion of the drug molecule that is responsible for the biologic activity of the drug. 

Because skin exhibits many of the properties of a lipid membrane, dermal penetration can often be enhanced by increasing a molecule s lipophilicity. Preparation of an ester of an alcohol is often used for this purpose since this stratagem simultaneously time covers a hydrophilic group and provides a hydrophobic moiety the ready cleavage of this function by the ubiquitous esterase enzymes assures availability of the parent drug molecule. Thus acylation of the primary alcohol in flucinolone (65) with propionyl chloride affords procinonide (66) the same transform... 

Cannabinoids were used in medicine in the form of their crude extracts many centuries ago. Lately the use of cannabis for so-called recreational purposes has become a national vice of substantial proportions. Several attempts have been made to focus the potentially useful pharmacological properties of marijuana into drug molecules with no abuse potential. 

Molecular mechanics calculations have proved to be enormously useful in pharmaceutical research, where the complementary fit between a drug molecule and a receptor molecule in the body is often a key to designing new pharmaceutical agents (Figure 4.18). 

Pharmacological hypotheses are the most rigorously tested in all of biological science. A potential drug molecule... 

FIGURE 41 -1. Calcium channel blockers inhibit the movement of caldum ions across the cell membrane. When calcium channels are blocked by drug molecules, musde contraction is decreased, causing the smooth musdes of the arteries and arterioles to dilate. 

This is illustrated in Scheme VI. The protected glyceryl derivatives are insoluble in aqueous media and appear to be hydrolytically stable. The deprotected species (structure 27) is water-soluble and hydrolyzes in aqueous media at neutral pH at 37°C to give glycerol, phosphate, and ammonia. The free hydroxyl units of the deprotected polymer provide sites for the covalent attachment of drug molecules. Water insolubility can be imparted by the use of appropriate hydro-phobic cosubstituent groups to generate solid, erodible materials. 

We have already seen how water solubility and hydrolytic degradability can be built into the carrier macromolecule by the use of specific side groups. Here we will review an additional way in which drug molecules have been Linked to polyphosphazenes—by coordination. 

The structural versatility of pseudopoly (amino acids) can be increased further by considering dipeptides as monomeric starting materials as well. In this case polymerizations can be designed that involve one of the amino acid side chains and the C terminus, one of the amino acid side chains and the N terminus, or both of the amino acid side chains as reactive groups. The use of dipeptides as monomers in the manner described above results in the formation of copolymers in which amide bonds and nonamide linkages strictly alternate (Fig. 3). It is noteworthy that these polymers have both an amino function and a carboxylic acid function as pendant chains. This feature should facilitate the attachment of drug molecules or crosslinkers,... 

The law of mass action has been successfully applied to many drug dose-response relationships since the early work of Clark. The systematic relation between the dose of a drug and the magnitude of its response is based on three assumptions (1) response is proportional to the level of receptor occupancy (occupancy theory), (2) one drug molecule combines with one receptor site, and (3) a negligible fraction of total drug is combined with the receptors. These assumptions must also apply to Beidler s equation. 

Thus, the biological activity of a drug molecule could be expressed as a function of its electronic, hydrophobic, and steric properties, and one or more such factors as hydrogen bonding or polarizability (x) which might be involved. 

Cyclopropane rings are commonly found in biologically active natural products and therapeutic drug molecules [50-52]. Iron porphyrins are active catalysts for the... 

Fischer, H., Kansy, M., Bur, D. CAFCA a novel tool for the calculation of amphiphilic properties of charged drug molecules. Chimia 2000, 54, 640-645. 

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