A versatile synthesis of multiply substituted cyclic dipeptides has been designed, based on the stepwise construction of the piperazine-2,5-dione ring using molecular fragments from four different precursor molecules. Starting from substituted 2-allylanilines, reaction with me...
Autor(es): Alirio Palma. Lina Maria Acosta. Christopher Glidewell.
Introduction: There are not effective drugs available for treatment of dengue fever despite intensive research on synthetic inhibitors. The search for active phytochemicals could serve for the discovery of new drugs. This study aims to evaluate the antiviral activity in vitro of ...
Autor(es): Elena Stashenko. Raquel Elvira Ocazionez Jiménez.
Six Lippia sp. were subjected to sequence analysis of the small ribosomal subunit (SRS) or 18S rDNA gene (ca. 1530 bp in length) for studying their genetic relationship. A total of nine nucleotide differences distinguished the species-specific SRS haplotypes of L. alba, L. americ...
Autor(es): Elena Stashenko. Fernando Rondón González. Liliana Santamaría Acevedo. César Augusto Prada Medina. Francisco José Martínez Pérez. Jorge Luis Fuentes Lorenzo.
Lichens are symbiotic associations of fungi with microalgae and/or cyanobacteria, which are considered among the slowest growing organisms, with strong tolerance to adverse environmental conditions. There are about 400 genera and 1600 species of lichens and those belonging to the...
Autor(es): Elena Stashenko. Édgar Nagles. Alberto Cornejo Mora. Alejandro Ardiles.
Petroporphyrins are biomarkers derived from chlorophyll, bacteriochlorophyll and the heme group, commonly present in crude oils as vanadyl or nickel complexes. These compounds, which despite of the organic matter maturation process preserve the tetrapyrrolic core of their precurs...
Autor(es): Cristian Blanco. Marianny Yajaira Combariza.