Antifertility agents

Oral contraceptive medications are among the most prescribed and effective drugs. The failure rates associated with various methods of contraception are cited in the following table. 

The most common type of oral contraceptive is the combination preparation and these are listed in Table 61.5. 

The antifertility agents suppress ovulation by the following methods  

The following are the various adverse metabolic effects of oral contraceptives. 

The potential benefits of oral contraceptive use consist of the following  

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The hydrolysis and alcoholysis reactions have been extended to the heterocyclic series. A systematic study has been published of the hydrolysis of unsaturated oxazolones derived from a selection of heterocyclic aldehydes. A detailed study of the synthesis and stereospecific hydrolysis and methanolysis of the (Z) and ( ) isomers of 2-methyl (or phenyl)-4-(thienylmethylene)-5(4F/)-oxazo-lones 435 and 437 has also been described (Scheme 7.144). The synthesis of 2-acylamino-3-(indol-3-yl or carbazol-3-yl)acryhc acid derivatives as potential antifertility agents via oxazolone hydrolysis has also been published. ... 

The Chinese reports that gossypol may act as an antifertility agent in men (218) have renewed Interest in this and related compounds. 

National Coordinating Group on Male Antifertility Agents (China) Gynecol, obstet. Invest. 1979, 1 > 163. 

Jones, A.R. O Brien, R.W. (1980) Metabolism of three active analogues of the male antifertility agent a-chlorohydrin in the rat. Xenobiotica, 5, 365-370 Kaplan, D.L., Cornell, J.H. Kaplan, A.M. (1982) Biodegradation of glycidol and glycidyl nitrate. Appl. environ. Microbiol., 43, 144-150... 

National Coordination Group on Male Antifertility Agents, Chinese Med. J., 4 (1978) 417. 

Orally effective antifertility agent Potent oral progestin, mild androgenic effect Used as an antifertility agent Potent progestin... 

The influence of such variables as age, sex, smoking, ethanol, oral antifertility agents, total calories, the relative proportion of the macromolecular constitutents of the diet, exercise, and environmental exposure to certain prevalent chemicals would eventually need to be recognized and to some extent tested before the generality of any conclusions drawn in one group of subjects could be extended to other groups. Also, as previously emphasized, normal subjects under... 

Steinberger, E. Potential male antifertility agents, pp. 33-49. In F.G. McMahon, Ed. Endocrine-Metabolic Drugs. Vol. VI. New York Futura, 1974. 

This methodology was used for synthesis of the sesquiterpene ( )-3 from the unsaturated ketone 1 via 2. The natural product (12S)-3 is an antifertility agent in mice. 

The use of chemical antifertility agents or chemosterilants with attractants is being explored. Insects made infertile by this combination would be more damaging to their species than if they were killed outright 11,12), since they would seek out and mate with other members of their species and thereby prevent them from propagating— setting up, in effect, an entomological chain reaction. 

The natural product gossypol, [45], a polyphenolic binaphthyl, is a male antifertility agent of considerable current interest. The available evidence suggests that the antifertility action of [45] may reside only in the (-) enantiomer (225). Procedures have been devised for the chromatographic separation of the enantiomers of [45] as diastereomeric derivatives of optically active (i-amino alcohols (226,227). L-Phenylalaninol was used in one procedure (227), whereas (—)-norepinephrine was employed in... 

The f-butylated naphthalene derivative (18 equation 49) is of interest as an intermediate for the synthesis of fungicides. Tetrahydronaphthalene derivatives, such as (20), have been evaluated as antifertility agents. Sugita et al. have studied the AlCb-catalyzed Friedel-Crafts alkylation of benzene with l-phenyl-2-propanol and 2-phenyl-1-propanol in the presence of additives, such as CuCb, CU2CI2 and decalin. Highly regioselective formation of 1,1-diphenylpropane was observed with Cu or Cu chloride as the additive. Some pertinent results of synthetic value are shown in Scheme 5. The addition of decalin diminished the alkylation reaction to give Ae reduction product 1-phenylpropane. 

Defatting creates cell necrosis. Nematocides also reduce cell P450 content. Sulphyril, but not glutathione, mediates toxic effects. Biotransformation (hydrolysis and oxidation) is via the mercapturic acid route, producing a-chlorohydrin and a-bromohy-drin, two antifertility agents. Further oxidation of these substances may produce oxalic acid, which causes liver and kidney damage. 

Sulprostone (CP-34,089, ZK 57,671, SHB 286, 14) was 10-30X more active than PGE2 as an antifertility agent in laboratory studies but equal... 

A review of adrenergic innervation of the manunalian oviduct includes a summary of drugs that modify the sympathetic nervous system and affect ovum transport and fertility.125 plants are a relatively untapped potential source of new antifertility agents.126... 

Despite its extremely useful contributions to the modem pharmacopoeia such as artemisin and huperzine, folk medicine is a rather unreliable guide in the search for new medicines. This is illustrated by the example of antifertility agents according to natives of some islands of the Pacihc,... 

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