Now showing items 41-50 of 69
Ethyl propionate: Synergistic kairomone for african palm weevil,Rhynchophorus phoenicis L. (Coleoptera: Curculionidae)
Small trunk pieces of a freshly felled 10-year-old oil palm,Elaeis quineensis (Jacq.), were placed in a modified Nalgene desiccator, and volatiles captured for six days on Porapak Q. Gas chromatographic (GC) analysis of ...
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.
Aggregation Pheromone of Coconut Rhinoceros Beetle, Oryctes rhinoceros (L.) (Coleoptera: Scarabaeidae)
Male coconut rhinoceros beetles,Oryctes rhinoceros (L.), produce three sex-specific compounds, ethyl 4-methyloctanoate, ethyl 4-methylheptanoate, and 4-methyloctanoic acid, the first of which is an aggregation pheromone. ...
Structure, chirality, and field testing of a male-produced aggregation pheromone of Asian palm weevilRhynchophorus bilineatus (Montr.) (Coleoptera: Curculionidae)
4-Methyl-5-nonanol is a male-produced aggregation pheromone of the Asian palm weevil,Rhynchophorus bilineatus (Montr.). The pheromone was identified by coupled gas chromatographic-electroantennographic detection (GC-EAD) ...
Sudoku Puzzles for First-Year Organic Chemistry Students
We use sudoku puzzles to help the students (i) learn the correspondence between the names of the amino acids, their abbreviations, and codes and (ii) learn the correspondence between the names of the functional groups, ...
Reactivity and structure of derivatives of 2-hydroxy-1,4-naphthoquinone (lawsone)
The structures of two derivatives of 2-hydroxy-1,4-naphthoquinone (lawsone) are examined using the density functional theory (DFT) hybrid functional B3LYP. Using the optimized structure of lawsone acetate, the reactivity ...
Sex pheromone components of Diatraea considerata (Heinrich) (Lep., Pyralidae)
Three aldehydes. (Z)-11-hexadecenal (Z11–16:Ald), (Z)-7-hexadecenal (Z7–16:Ald) and (Z)-13-octadecenal (Z13–18:Ald), in a ratio of 74:23:3 are female-produced sex pheromone components of the pyralid moth, Diatraea considerata ...
Synthesis of 2-hydroxy-3-substituted naphthoquinones using the Heck reaction
An efficient Heck coupling of 2-hydroxy-3-iodo-naphthoquinone with a series of electron-deficient alkenes in aqueous solution has been accomplished. The method is characterized by simple conditions and facile work-up to ...
Removal of both N-nitrosodimethylamine and trihalomethanes precursors in a single treatment using ion exchange resins
Drinking water utilities are relying more than ever on water sources impacted by wastewater effluents. Disinfection/oxidation of these waters during water treatment may lead to the formation of several disinfection ...
The role of chloramine species in NDMA formation
N-nitrosodimethylamine (NDMA), a probable human carcinogen disinfection by-product, has been detected in chloraminated drinking water systems. Understanding its formation over time is important to control NDMA levels in ...