The phenomenon whereby certain chemical compounds have structures that are different although the compounds possess the same elemental composition. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
Isomerisms
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Methods
A series of steps taken in order to conduct research.
Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. (From Stedman, 25th ed)
Methylations
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Estrenes
Unsaturated derivatives of the ESTRANES with methyl groups at carbon-13, with no carbon at carbon-10, and with no more than one carbon at carbon-17. They must contain one or more double bonds.