Now showing items 1-10 of 41
Efficient syntheses of streptocarpone and (±)-a-dunnione
An efficient divergent synthesis of both streptocarpone and racemic α-dunnione from lawsone are described. A one-pot, formal [3+2] cyclization to form a furanonaphthoquinone directly provided a common intermediate.
Light Reflection by Cuticles of Chrysina Jewel Scarabs: Optical Measurements, Morphology Characterization, and Theoretical Modeling
Cuticles of some Chrysina scarabs are characterized by flat, graded, and twisted structures of nanosized chitin fibrils. As inferred from SEM images, each species has its own spatial period or pitch P which is dependent ...
Bioassay-guided isolation of anti-inflammatory O-sulfated withanolides from Acnistus arborescens (Solanaceae)
Bioassay-guided fractionation of Acnistus arborescens (Solanaceae) organic extract afforded two anti-inflammatory withanolides: 2,3-Dihydro-3β-O-sulfate withacnistin (1) and 2,3-Dihydro-3β-O-sulfate withaferin A (2) showing ...
Synthesis of Iodinated Naphthoquinones Using Morpholine-Iodine Complex
(Synthetic Communications Vol. 34, No. 18, pp. 3389–3397, 2004, 2004)
The efficient synthesis of 2‐hydroxy‐3‐iodo‐1,4‐naphthoquinone (3), 2‐amino‐3‐iodo‐1,4‐naphthoquinone (4), and 2‐iodo‐1,4‐naphthoquinone (5) have been developed using the parent naphthoquinone in combination with the ...
Influence of rice field agrochemicals on the ecological status of a tropical stream
Many tropical countries contain a high density of protected ecosystems, and these may often be bordered by intensive agricultural systems. We investigated the chemical and ecological status of a stream connecting an area ...
Metals in coastal mollusks of Costa Rica
Metales en moluscos costeros de Costa Rica
The input of contaminants to coastal ecosystems is a global problem on the rise. Data on metal pollution from tropical sites is often lacking and pilot surveys are urgently needed to provide a general framework to estimate ...
Pristine but metal-rich Río Sucio (Dirty River) is dominated by Gallionella and other iron-sulfur oxidizing microbes
Whether the extreme conditions of acidity and heavy metal pollution of streams and rivers originating in pyritic formations are caused primarily by mining activities or by natural activities of metal-oxidizing microbes ...
Homopropargyl alcohol 1,1-diphenylbut-3-yn-1-ol
The asymmetric unit of the title compound, C16H14O, contains one molecule with a central carbon atom having a distorted tetrahedral geometry made of a propargylic fragment, a hydroxy group and two aromatic rings. ...
Harnessing titanium dioxide surface toward novel functional materials
The ever-increasing worldwide energy consumption has led the society to quest for novel and functional materials that can be used in the development of solar fuels to some extent lessen the dependence on fossil fuels. In ...
Dye‐sensitized Devices: Photovoltaic and Photoelectrolytic Applications
Dye‐sensitized approach along with stability and surface robustness in titanium dioxide (TiO2) against photocorrosion and degradation has been widely studied and applied in several important applications. This chapter ...