A monoclinic polymorph of 3,7,7-trimethyl-1-phenyl-5,6,7,8-tetrahydro-1H-pyrazolo[3,4-b]quinolin-5-one.

A second, monoclinic, polymorph of the title compound, C19H19N3O, is reported. In this polymorph, the molecules are linked into chains by paired C-H..

3-tert-Butyl-7,7-dimethyl-1-phenyl-5,6,7,8-tetrahydroimidazo[3,4-b]quinolin-5-one and 2,8,8-trimethyl-5-phenyl-6,7,8,9-tetrahydroimidazo[2,3-a]quinolin-6-one: chains generated by C-H...N hydrogen bonds.

In both 3-tert-butyl-7,7-dimethyl-1-phenyl-5,6,7,8-tetrahydroimidazo[3,4-b]quinolin-5-one, C22H25N3O, (I), and 2,8,8-trimethyl-5-phenyl-6,7,8,9-tetrahydroimidazo[2,3-a]quinolin-6-one, C19H19N3O, (II), the heterobicyclic portions of the molecules are planar, with naphthalene-type delocalization in (II), while the carbocyclic ring in each compound adopts an envelope conformation. In both (I) and (II), the molecules are linked weakly into chains by a single C-H..

Molecular conformation and supramolecular aggregation in two fused pyrazoles: pi-stacked R(2)(2)(6) dimers in 2,8,8-trimethyl-6,7,8,9-tetrahydropyrazolo[2,3-a]quinazolin-6-one, and sheets of alternating R(2(2)12) and R(6)(6)(48) rings in 3-tert-butyl-4',4'-dimethyl-1-phenyl-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-b]pyridine-5-spiro-1'-cyclohexane-2',6'-dione.

In 2,8,8-trimethyl-6,7,8,9-tetrahydropyrazolo[2,3-a]quinazolin-6-one, C(13)H(15)N(3)O, (I), the heterobicyclic system is planar and exhibits peripheral ten pi-electron delocalization. In 3-tert-butyl-4',4'-dimethyl-1-phenyl-4,5,6,7-tetrahydro-1H- pyrazolo[3,4-b]pyridine-5-spiro-1'-cyclohexane-2',6'-dione, C(23)H(25)N(3)O(2), (II), the pyrazole ring exhibits marked bond fixation, while the reduced pyridine ring adopts a half-chair conformation. Molecules of (I) are linked into centrosymmetric R(2)(2)(6) dimers by a single C-H.

Influence of number of pregnancies and total breast-feeding time on bone mineral density.

Objective: To analyze how the number of pregnancies and total breast-feeding time influence bone mineral density.

Methods: 50 healthy women aged 35 to 40 years were studied. Weight, height, number of term pregnancies, time since last pregnancy and breast-feeding time were analyzed.