Aminopyrimidine-carboxyl(ate) interactions in trimethoprim maleate, an antifolate drug.

In the title cocrystal, trimethoprim maleate [2,4-diamino-5-(3,4,5-trimethoxybenzyl)pyrimidin-1-ium maleate], C(14)H(19)N(4)O(3)(+).C(4)H(3)O(4)(-), the trimethoprim molecule is protonated at N1. The carboxyl group of the maleate ion makes a specific double hydrogen bond of type N-H.O with the 2-amino group and the protonated N1 atom of the trimethoprim cation which is similar to the carboxylate-trimethoprim cation interaction observed in the complex of dihydrofolate reductase with trimethoprim. The pyrimidine moieties of trimethoprim cations are centrosymmetrically paired through a pair of N-H.N hydrogen bonds involving the 4-amino group and the pyridinium N3 atom of a symmetry-related molecule. One of the O atoms at the maleate carboxylate group bridges the 2-amino and 4-amino groups on either side of the paired trimethoprim cations. The other O atom of the carboxylate group forms an intramolecular O-H.O hydrogen bond with the carboxyl group. These characteristic hydrogen bonds result in infinite two-dimensional aggregation of rings into a supramolecular ladder, which is further crosslinked through weak C-H.O interactions with methoxy groups of neighbouring trimethoprim molecules to form a layered structure.

Discriminant analysis of WAIS results in different types of dementia and depressed patients.

A Multivariate Analysis of Covariance and Discriminant Analysis were carried out on complete WAIS profiles obtained from three groups of demented patients: Multi-Infarct Dementia patients, Senile Dementia of Alzheimer Type patients, and Alcoholic Dementia patients. A group of middle-aged Depressed patients was also included. WAIS did not differentiate among dementias, but Picture Completion and Block Design subtests proved to be effective in differentiating dementia from depression.

[Analysis of the effect of lithium salts on cognitive functions]. / Analisi dell'influenza dei sali di litio su alcune funzioni cognitive.

In this work the authors studied the effects of lithium on memory and reaction times in 7 manic-depressive patients receiving long-term therapy. The results suggest lithium treatment does not change these intellectual functions to any significant extent, comparing the trials of the experimental sessions during the therapy and after two weeks off lithium. Our data mostly agree with the studies of other Authors who used similar experimental methods.