Publications by authors named "Novoa de Armas H"

This study investigates 3 amorphous technologies to improve the dissolution rate and oral bioavailability of flubendazole (FLU). The selected approaches are (1) a standard spray-dried dispersion with hydroxypropylmethylcellulose (HPMC) E5 or polyvinylpyrrolidone-vinyl acetate 64, both with Vitamin E d-α-tocopheryl polyethylene glycol succinate; (2) a modified process spray-dried dispersion (MPSDD) with either HPMC E3 or hydroxypropylmethylcellulose acetate succinate (HPMCAS-M); and (3) confining FLU in ordered mesoporous silica (OMS). The physicochemical stability and in vitro release of optimized formulations were evaluated following 2 weeks of open conditions at 25°C/60% relative humidity (RH) and 40°C/75% RH.

View Article and Find Full Text PDF

A convergent and versatile Vilsmeier-Haack-based carbo-annulation strategy that exhibits an unusually elevated bond-forming efficiency has been developed. By virtue of its innovative approach, structure economy and simple execution conditions the methodology reported here constitutes a very attractive protocol that enables the rapid assembly of structurally diverse quinazoline chemotypes.

View Article and Find Full Text PDF

Elevated plasma levels of plasminogen activator inhibitor-1 (PAI-1) have been correlated with cardiovascular diseases such as myocardial infarction and venous thrombosis. PAI-1 has also been shown to play an important role in tumor development, diabetes, and obesitas. Monoclonal antibodies MA-8H9D4 and MA-56A7C10, and their single-chain variable fragments (scFv), exhibit PAI-1-neutralizing properties.

View Article and Find Full Text PDF

In the title compound, C(6)H(8)N(2)O(2)S, also known as N-acetyl-2-thiohydantoin-alanine, the molecules are joined by N-H...

View Article and Find Full Text PDF

The title compound, (C(6)H(5)CH(2))(3)PO, is an organic tertiary phosphine oxide. The molecule has threefold symmetry, with the P-O bond along the threefold axis. Main dimensions include P-O 1.

View Article and Find Full Text PDF

The three-dimensional structure of Azospirillum irakense pectate lyase (PelA) has been determined at a resolution of 2.65 A. The crystals are hexagonal, belonging to space group P6(5)22, with unit-cell parameters a = b = 85.

View Article and Find Full Text PDF

The PelA gene from the N(2)-fixing plant-associated bacterium Azospirillum irakense encodes a pectate lyase. Analysis of the corresponding amino-acid sequence revealed no homology to other bacterial, plant and fungal pectinases of known published structure, resulting in the classification of the enzyme in a new pectate lyase family. The A.

View Article and Find Full Text PDF

MornigaM, a lectin from Morus nigra, belongs to the mannose-binding subgroup of the family of jacalin-related plant lectins. It was crystallized in the P6(5) space group, with unit-cell parameters a = b = 110.74, c = 159.

View Article and Find Full Text PDF

Secnidazole (hydroxy-2-propyl)-l-methyl-2-nitro-5-imidazole) is an antimicrobic agent. This drug has pharmacological activity against intestinal and hepatic amebiasis, giardiasis and vaginal trichomoniasis. This paper shows the physicochemical parameters of secnidazole determined during a preformulation study.

View Article and Find Full Text PDF

The title compound, C8H7NO3, is an aromatic amide that forms an extensive hydrogen-bond network within the crystal. The crystals were obtained while preparing derivatives of benzoic acid as intermediaries in the synthesis of acridones.

View Article and Find Full Text PDF

In the title compound, C(28)H(38)N(4)O(6), the 4-aryl substituent occupies a pseudo-axial position approximately orthogonal to the plane of the dihydropyridine ring [88.1 (3) degrees ]. The dihydropyridine ring adopts a flattened boat conformation.

View Article and Find Full Text PDF

The title compound, C(9)H(11)NO(3)S, has crystallographic mirror symmetry, occurs in the thiocarbamate form and is stabilized in an s-cisoid,s-transoid conformation with respect to the C-N-C group. There are two intramolecular hydrogen bonds, one between the H atom of the N-H group and the O atom of the furan ring, and the other between the H atom of the secondary carbon of the isopropyl group and the S atom. The packing of the molecules is assumed to be dictated by van der Waals interactions.

View Article and Find Full Text PDF

The purpose of this research is to characterize the possible vascular selectivity of a series of novel bicyclic compounds derived from 3,4-dihydropyridones. We describe the synthesis, structural study by X-ray analysis and quantum chemical calculations at semiempirical (AMI) and ab initio (HF/321G) levels and pharmacological activity of these 4-aryl-7,7-dimethyl-2,5-dioxo-1,2,3,4,5,6,7,8-octahydroquinolines. In addition, the more favoured conformation for compounds 4a-c in solution was determined from the calculated and experimental proton coupling constants.

View Article and Find Full Text PDF