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Benjamin R. Chemel

Publications and source records attributed to Benjamin R. Chemel.

2 recordsLinked to original sources

The plant diversity sampling design for The National Ecological Observatory Network

The National Ecological Observatory Network (NEON) is designed to facilitate an understanding of the impact of environmental change on ecological systems. Observations of plant diversity—responsive to changes in climate, disturbance, and land use, and ecologically linked to soil, biogeochemistry, and organisms—result in NEON data products that cross a range of organizational levels. Collections include samples of plant tissue to enable investigations of genetics, plot‐based observations of incidence and cover of native and non‐native species, observations of plant functional traits, archived vouchers of plants, and remote sensing airborne observations. Spatially integrating many ecological observations allows a description of the relationship of plant diversity to climate, land use, organisms, and substrates. Repeating the observations over decades and across the United States will iteratively improve our understanding of those relationships and allow for the testing of system‐level hypotheses as well as the development of predictions of future conditions.

Ecosphere

Analogues of doxanthrine reveal differences between the dopamine D1 receptor binding properties of chromanoisoquinolines and hexahydrobenzo[a]phenanthridines

Efforts to develop selective agonists for dopamine D 1 -like receptors led to the discovery of dihydrexidine and doxanthrine, two bioisosteric β-phenyldopamine-type full agonist ligands that display selectivity and potency at D 1 -like receptors. We report herein an improved methodology for the synthesis of substituted chromanoisoquinolines (doxanthrine derivatives) and the evaluation of several new compounds for their ability to bind to D 1 - and D 2 -like receptors. Identical pendant phenyl ring substitutions on the dihydrexidine and doxanthrine templates surprisingly led to different effects on D 1 -like receptor binding, suggesting important differences between the interactions of these ligands with the D 1 receptor. We propose, based on the biological results and molecular modeling studies, that slight conformational differences between the tetralin and chroman-based compounds lead to a shift in the location of the pendant ring substituents within the receptor.

European Journal of Medicinal Chemistry