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Biomedical subjects

A M Omar

Publications and source records attributed to A M Omar.

At least 37 records · Page 2Linked to original sources
PubMed1981

Thiourea and thiosemicarbazide derivatives structurally related to hexestrol: synthesis and anticancer and other pharmacological properties.

Two novel series of thio compounds bearing internal structural modifications of hexestrol were synthesized as potential anticancer agents. The first contains several N-substituted thiourea functions, and the second contains various N4-substituted-3-thiosemicarbazide moieties in place of one alpha-ethyl group of hexestrol dimethyl ether. The products showed no antileukemic activity in the P-388 lymphocytic leukemia system and did not exhibit any anticonvulsant or estrogenic properties.

Animals↗
PubMed1980

Synthesis of novel hexestrol and diethylstilbestrol derivatives as potential anticancer and estrogenic agents.

Two novel series of potential anticancer agents derived from hexestrol and diethylstilbestrol have been synthesized. The first includes several alkylating agents containing sulphonic esters and nitrogen mustard functions attached through various chains to only one phenolic group in hexestrol. The second contains the N1-acetyl-N4-substituted thiosemicarbazide moieties attached to one phenolic group hexestrol or to the two phenolic oxygens in diethylstilbestrol. The tests of some of the products for antileukemic activity in P 388 Lymphocytic Leukemia indicated no significant activity over the parent nuclei. The estrogenic activity of some representative examples of the thiosemicarbazides was found to be dependent on the nature of the N4-substituent in the thiosemicarbazide moiety.

Animals↗
PubMed1980

Novel potential anticancer agents derived from benzimidazole.

Two novel series of benzimidazole derivatives bearing structural modifications of certain drugs were prepared for evaluation for potential anticancer activity. The first series was a group of alkylating agents, and the second series was a variety of 4-substituted-1-thioacetyl-3-thiosemicarbazides. The tests of some representative products for antileukemic activity against P-388 lymphocytic leukemia indicated no significant effects.

Animals↗
PubMed1978

Behaviour of hepatitis B antigen in bilharzial patients infected with HBs positive viral hepatitis.

A TOTAL of 204 cases with acute viral hepatitis were studied: 93 bilharzial and 111 non-bilharzial. This study is concerned with the 106 cases showing positive HBS Ag test. Follow up of the cases after discharge from the Fever Hospital was carried out by repeated clinical and laboratory examinations 3 montly in the first year and 6 monthly subsequently. The bilharzial and non-bilharzial patients were found to be equally susceptible to HBS Ag positive hepatitis (p=0.25). However, antigenaemia tended to last longer as a whole in the bilharzial patients (p=0. 005) and was not affected by successful specific antibilharzial treatment. It seems that bilharzial infection predisposes to "retention" of HBs antigen, after subsidance of the acute attack, thus increasing the volume of reservoir for HB virus in our rural community.

Acute Disease↗
PubMed1977

Potential steroidal antiestrogens.

A series of analogues of 17beta-estradiol has been synthesized and the compounds have been tested, using sucrose density gradient analysis, for their ability to compete with [6,7-3H]-17beta-estradiol for the estrogen-receptor protein from mouse uterine homogenates. Active compounds were also tested for antiuterotrophic activity in immature rats and/or mice. 3,17beta-Dihydroxy-6-phenylestra-1,3,5(10),6-tetraene (14) was the most active new compound in the in vitro test suppressing the binding of 17beta-estradiol by 34 and 87%, respectively, at molar ratios of 1 and 3.16. It was significantly more potent than the intermediate 6-oxoestradiol (4) which produced a 52% inhibition of binding at a molar ratio of 3.16. The thiosemicarbazone of 6-oxoestradiol (17) and the derived 3,17beta-dihydroxy-6-(2-imino-4-oxothiazolidinyl-1-imino)estra-1,3,5(10)-triene (19) produced, respectively, only 46 and 16% inhibition of binding at a molar ratio of 10. Introduction of a 1-methyl substituent into either 6-oxo or 6-phenyl compounds reduced affinity for the receptor significantly (compounds 5 and 15) and conversion of the 3-OH into a beta-dialkylaminoethoxy group virtually destroyed all binding activity (compounds 2, 6, 10, and 11). At a molar ratio of 10 compound 14 failed to suppress the uterine weight response of immature rats to 17beta-estradiol, whereas compound 15, at a molar ratio of 200, produced a significant increase in the uterine weight of immature rats but not of immature mice even at a molar ratio of 1000.

Animals↗
PubMed1977

The cyclodesulphurization of thio-compounds. Part 15: Synthesis of 6-substituted aminophenanthridines from some thiourea derivatives.

Several N-alkyl, aryl, and aralkyl-N'-2-biphenylthiourea derivatives have been synthesized and cyclodesulphurized into the corresponding 6-substituted aminophenanthridines. The ring closure was brought about with mercuric chloride, phosphoryl chloride or polyphosphoric acid. Phosphoryl chloride was found to be the most efficient in inducing ring closure and producing the highest yield of cyclized products. The results of study on the cyclodesulphurization reaction mechanism suggested the formation of a carbodiimide intermediate and identified some of the organic mercurials involved in the various stages of the reaction.

Cyclization↗
PubMed1976

The cyclodesulphurization of thio-compounds. Part 12: A new simple method for the synthesis of N-alpha-substituted benzimidazoles from thiourea derivatives.

A new facile method has been established for the synthesis of N-alpha-substituted benzimidazoles by cyclodesulphurization of various N-[2-amino]-phenyl-N'-alkyl, -aryl and -aralkylthiourea derivatives with mercuric salts. Besides mercuric chloride, the use of mercuric oxide and mercuric acetate was successful for the first time in effecting ring closure of thio-compounds. The attempted use of acid condensing agents showed phosphoryl chloride to be less efficient than mercuric salts in conducting the cyclization reactions and led to poor yields of cyclized products.

Benzimidazoles↗
PubMed1975

On the relation between testes size and sperm reserves in the one-humped camel (camelus dromedarius).

The size, weight and volume as well as the sperm content of the testes of 18 mature, 6-10-year-old camels with unknown breeding history were determined after slaughtering and then related to one another. It was found that the weight and the volume of the testes can be estimated fairly accurately by means of their length. The length of the testes can also be used to calculate the sperm reserves, although more accurate values can be obtained by taking the square numbers of the testes length, breadth, and thickness into account. The average values for gonadal and epididymal sperm reserves of paired testes and epididymides was 6.278 +/- 1.226 X 10(9) and 12.177 +/- 2.316 X 10(9) respectively. The sperm production per gram testes tissue was 40.55 +/- 15 X 10(6).

Animals↗