Abstract: A pharmaceutical composition is disclosed comprising (-)-cis-2-methylspiro(1,3-oxathiolan-5,3')quinuclidine, and/or the pharmaceutically compatible acid addition salts thereof, together with at least one of physostigmine, tetrahydroaminoacridine, choline, lecithin, piracetam, aniracetam, pramiracetam, oxiracetam, 4-aminopyridine, 3,4-diaminopyridine, somatostatin, pirenzepine, N-methylatropine, N-butylscopolamine, scopolamine, clonidine, quanfamicine and Nerve Growth Factor. Also disclosed is a method for treating senile dementia of Alzheimer's type, which comprises coadministering to a patient in need thereof an effective dose of the spiro compound together with at least one other compound selected from those listed above.

Abstract: The (+)-cis-, (-)-cis-, (+)-trans- and (-)-trans- forms of 2-methylspiro(1,3-oxathiolan-5,3')quinuclidine are prepared by optical resolution of each of the (.+-.)-cis- and (.+-.)-trans-isomers. These compounds find application in treating diseases of the central nervous system in mammals, especially diseases due to a deficiency in the central cholinergic system. Biological tests indicate that the (-)-cis-form, as well as the (.+-.)-cis-isomer, shows particular promise for treating senile dementia of Alzheimer's type.

Abstract: Quinuclidine derivatives having the general formula (I) ##STR1## and geometrical isomers, enantiomers, diastereoisomers, racemates and/or acid addition salts thereof, wherein Z represents the group >CR.sup.1 R.sup.2 or two hydrogen atoms; and R.sup.1 and R.sup.2, which may be identical or different, are each alkyl, cyclopentyl, cyclohexyl, aryl, or diarylmethylol, or alkyl which is substituted by one or more aryl groups, or one of R.sup.1 and R.sup.2 may be hydrogen.

Abstract: Organo-phosphorus compounds of the general formula ##STR1## wherein Z is a member selected from ##STR2## wherein R and R' are each selected from hydrogen and lower alkyl, R" designates a member selected from methyl and ethyl, and X.sup.- is an anion may be used as active ingredient in pharmaceutical and pesticidal, especially acaricidal and fungicidal, compositions of matter of low mammalian toxicity.