Biomedical subjects

P J Machin

Publications and source records attributed to P J Machin.

5 recordsLinked to original sources

PubMed1991

Romazarit: a potential disease-modifying antirheumatic drug.

The synthesis of a series of substituted heterocyclic alkoxypropionic acids is described. They were evaluated for antiinflammatory effects in two animal models of chronic inflammation; adjuvant arthritis and type II collagen arthritis in the rat. The desired profile of biological activity was characterized by the reduction of inflammation with the coincident restoration toward normal levels of the biochemical markers (acute phase proteins) associated with the inflammatory response, an effect that was not shared by classical nonsteroidal antiinflammatory agents. Romazarit, (Ro 31-3948, 7), 2-[[2-(4-chlorophenyl)-4-methyl-5-oxazolyl]methoxy]-2-methylpropio nic acid, was selected for further evaluation. In contrast to NSAIDs, romazarit was inactive in animal models of acute inflammation, and furthermore it did not inhibit the cyclooxygenase enzyme in vitro or in vivo. Inhibition of interleukin-1-mediated events in vitro has been observed.

Animals↗

PubMed1990

Synthesis and antiviral activity of monofluoro and difluoro analogues of pyrimidine deoxyribonucleosides against human immunodeficiency virus (HIV-1).

A range of 2'-fluoro and 2',3'-difluoro analogues of pyrimidine deoxyribonucleosides have been synthesized and evaluated against human immunodeficiency virus (HIV-1) in a human lymphoblastoid cell line. Among these compounds, 1-(2,3-dideoxy-2-fluoro-beta-D-threopentofuranosyl)cytosine (12), 2',3'-didehydro-2',3'-dideoxy-2'-fluorocytidine (35), 1-(2,3-dideoxy-2,3-difluoro-beta-D-arabinofuranosyl)cytosine (41), and 3'-deoxy-2',3'-didehydro-2'-fluorothymidine (45) were found to have significant antiviral activity, with IC50 values of 0.65, 10, 10, and 100 microM, respectively. The structure-activity relationships are discussed.

Antiviral Agents↗

PubMed1985

Beta-adrenoceptor activity of the stereoisomers of the bufuralol alcohol and ketone metabolites.

The stereoisomers of 2-[(tert-butylamino)methyl]-7-methyl-2,7-benzofurandimethanol (2) and 2-[2-(tert-butylamino)-1-hydroxyethyl]-7-benzofuranyl methyl ketone (3), the alcohol and ketone metabolites of bufuralol, have been prepared and examined for beta-adrenoceptor activity in rats. All the stereoisomers with the S configuration hydroxylamine side chain showed potent beta 2-antagonist activity comparable to (S)-bufuralol (1a). In contrast, a wide range of antagonist potencies was observed at the beta 1-receptor; only alcohol diastereomer 9a was more active than 1a. This suggests that the shape of the 7-substituent in these benzofurans influences the degree of interaction with the beta 1-receptor much more than with the beta 2-receptor. Partial beta 1-agonist activity was associated not only with all the stereoisomers with the S configuration hydroxylamine side chain but also with some of the R configuration derivatives, especially (R)-ketone 3b. The results suggest that the margin of difference in beta-adrenoceptor activity between compounds epimeric at the hydroxylamine side chain can be significantly influenced by a suitable substituent in the aromatic nucleus.

Adrenergic beta-Antagonists↗

PubMed1984

Beta 1-selective adrenoceptor antagonists. 3. 4-Azolyl-linked phenoxypropanolamines.

A series of 4-substituted phenoxypropanolamines has been prepared and examined for beta-adrenoceptor activity. The 4-substituents, di- and triazole ring systems connected to the phenoxy ring by different length chains, were chosen as a means of introducing cardioselectivity. This has been achieved, especially in the 1-[4-[(4-chloropyrazol-1-yl)methoxy] phenoxy]-3-(isopropylamino)-2-propanol (11), the 4-[(2H-1,2,3-triazol-2-yl)methoxy] analogue (21), and the 4-[2-(2H-1,2,3-triazol-2-yl)ethoxy] analogue (22), which show potent beta 1-blockade with selectivity ratios in excess of 100:1. Structure-activity relationships are discussed, and the optimum position of the heteroatom in the 4-substituent is defined.

Adrenergic beta-Antagonists↗

PubMed1983

beta 1-selective adrenoceptor antagonists. 2. 4-ether-linked phenoxypropanolamines.

A series of 4-substituted phenoxypropanolamines was prepared and examined for beta-adrenoceptor activity. Some of the compounds, especially the [4-[2-[[2-(4-fluorophenyl)ethyl] oxy]ethoxy]phenoxy]propanolamines (14, 15, and 24), showed potent beta 1-blockade with virtually no beta 2-blockade at doses over a 1000 times greater. The compounds also possessed partial agonist activity. Structure-activity relationships are discussed, and conclusions are drawn about the binding sites on beta-adrenoceptors.

Adrenergic beta-Agonists↗