Abstract: Novel sterol derivatives of formula (I), in which: R1 represents a hydroxyl group or protected hydroxyl group, R2 represents a hydrogen atom and a double bond is present at c, or R1 and R2 together represent an oxo group and a double bond is present at b or double bonds are present at a and b; R3 represents a methyl group having ?- or ?-configuration; R4 and R5, which may be the same or different, are selected from hydrogen atoms and aliphatic, cycloaliphatic, araliphatic and aryl groups, or together with the nitrogen atom to which they are attached form a heterocyclic group; and X represents a polymethylene group containing 2–5 carbon atoms, an oxa group-containing analogue thereof in which a methylene group other than that attached to the —CO.NR4R5 moiety is replaced by an oxygen atom, or an unsaturated analogue thereof containing up to two double bonds.

Abstract: The invention is directed to a novel class of steroids which exhibit potent antiprogestational activity.

Abstract: The present invention provides new process of preparing neuromuscular blocking agents. The process include preparing neuromuscular blocking agents using the compounds of formula I: ##STR1## wherein R.sub.1 is .dbd.O and X is halo; and formula II: ##STR2## wherein R.sub.1 and X are as defined above.

Abstract: Method, compositions, and compounds for modulating brain excitability to alleviate stress, anxiety, insomnia and seizure activity using certain steroid derivatives that act at a newly identified site on the gamma-aminobutyric acid receptor-chloride ionophore (GR) complex.

Abstract: This invention provides a simplified method for converting pregnan-3,20-dione compounds to 3.alpha.-hydroxy,3.beta.-substituted-pregnanes. By selective use of reagents the unprotected dione is converted chemoselectively and diastereoselectively into a 3(R)-pregnan-3-spiro-2'oxirane-20-one intermediate. This intermediate can then be converted regioselectively by a second set of reactions to the 3.alpha.-hydroxy,3.beta.-substituted-20-one form, which can be further modified at the 20-keto position.Through this method, each ketone group is independently treated. By modifying the ketones one at a time, one can obtain the desired stereo-specificity at each site.

Abstract: Method, compositions, and compounds for modulating brain excitability to alleviate stress, anxiety, insomnia and seizure activity using certain steroid derivatives that act at a newly identified site on the gamma-aminobutyric acid receptor-chloride ionophore (GR) complex.

Abstract: Method, compositions, and compounds for modulating brain excitability to alleviate stress, anxiety, and seizure activity using certain steroid derivatives that act at a newly identified site on the gamma-ammobutyric acid/benzodiazepine receptor-chloride ionophore (GBR) complex.

Abstract: Method, compositions, and compounds for modulating brain excitability to alleviate stress, anxiety, and seizure activity using certain steroid derivatives that act at a newly identified site on the gamma-ammobutyric acid/benzodiazepine receptor-chloride ionpore (GBR) complex.

Abstract: Bisnaphthalimides of the formula I ##STR1## where X.sup.1 to X.sup.4 and R have the meanings stated in the description, and their preparation are described. The compounds are cytotoxic towards human cells in vitro.

Abstract: Method, compositions, and compounds for modulating brain excitability to alleviate stress, anxiety, and seizure activity using certain steroid derivatives that act at a newly identified site on the gamma-ammobutyric acid/benzodiazepine receptor-chloride ionpore (GBR) complex.