The total synthesis of a highly potent cytotoxic marine natural product, phorboxazole A, is described. Both a palladium(II)-mediated and a palladium(II)-catalyzed intramolecular alkoxycarbonylation were used as key steps for the preparation of the two cis-2,6-disubstituted tetrahydropyran rings (C22-C26 and C11-C15) of phorboxazole A.
The synthesis used a convergent approach involving...
This study evaluates the prediction of heat and moisture fluxes from a new land surface scheme with eddy correlation data collected at the old aspen site during the Boreal Ecosystem-Atmosphere Study (BOREAS) in 1994. The model used in this study couples a multilayer vegetation model with a soil model. Inclusion...
The rapid disruption of tropical forests probably imperils global biodiversity more than any other contemporary phenomenon¹⁻³. With deforestation advancing quickly, protected areas are increasingly becoming final refuges for threatened species and natural ecosystem processes. However, many protected areas in the tropics are themselves vulnerable to human encroachment and other environmental...
The relationships between types of wealth components and consumption
expenditures were investigated as a means of better understanding retired
elderly household well-being. Specifically, the concept of mental account was
used to identify the characteristics of different types of wealth components, and
four mental accounts were identified: flow of investment, current...
The potent antitumor agent phorboxazole A was synthesized from six subunits comprising C1-C2 (115), C3-C8 (98), C9-C19 (74), C20-C32 (52), C33-C41 (84) and C42-C46 (85). Tetrahydropyrans B and C containing cis-2,6-disubstitution were fabricated via palladium(II)-mediated intramolecular alkoxycarbonylation which, in the case of tetrahydropyran C, was carried out with catalytic palladium(II)...
The current study investigates gender differences in behavioral regulation in four societies: the United States, Taiwan, South Korea, and China. Directly assessed individual behavioral regulation(Head–Toes–Knees–Shoulders, HTKS), teacher-rated classroom behavioral regulation (Child Behavior Rating Scale, CBRS) and a battery of school readiness assessments (mathematics, vocabulary, and early literacy) were used with...
This research examines bargaining power in the market for Northeast
Multispecies Days-at-Sea (DAS). In 2004, the DAS system was converted
to a tradable input control system. Characteristics of the program include:
1) trading restrictions based on length and power to limit increases in
output, 2) prohibitions that limit the ability...
Computers have made a great contribution to the
design process in various applications, such as design
analysis and simulation. A new technology called
Computer-aided design (CAD) has helped the designer to
design and build very intricate systems.
While most of CAD software is run on workstations or
microcomputers with one...