Abstract: A process for the preparation of compounds of formula (I), wherein R is C2-C20 linear or branched alkyl, C3-C7 cycloalkyl, phenyl or benzyl, which can optionally be substituted by C1-C4 alkyl, halogen or C1-C4 alkoxy group, said process comprising: a) oxidation of eserine with hydrogen peroxide in the presence of a base and subsequent hydrolysis to geneseroline, without isolating the intermediate geneserine; b) acylation of geneseroline with an isocyanate of formula R—N═C═O, wherein R is as defined above, in the presence of a basic catalyst; c) optional transformation into a pharmaceutically acceptable salt. Compounds of formula (I) wherein R is a phenyl or benzyl, which can be optionally substituted by alkyl, halogen or alkoxy, are selective, potent brain anticholinesterase inhibitors.

Abstract: Alpha-olefin polymers and copolymers are prepared by polymerizing the monomers in the presence of a catalyst obtained by bringing into contact:a) a compound definable by the formula: ##STR1## wherein: M is represents a metal of group 4.beta. of the periodic table of elements;each R independently represents halogen atom; a linear or branched C.sub.1 -C.sub.10 alkyl group; or an aryl group; andeach Cp independently represents the cyclopentadienyl, indenyl or fluorenyl, group, possible carrying one or more C.sub.1 -C.sub.4 alkyl substituents, which Cp groups can also be connected together by a carbon atom or alkylsilane bridge structure;b) a trialkylaluminium: ##STR2## wherein each R' independently represents a linear or branched C.sub.1 -C.sub.10 alkyl group, or an aryl group; andc) a distannoxane: ##STR3## where each R" independently reprepsent a linear or branched C.sub.1 -C.sub.