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protoapigenone [Supplementary Concept]
has antineoplastic activity; isolated from Thelypteris torresiana; structure in first source
Date introduced: November 7, 2007
Flavones
A group of 4-keto-FLAVONOIDS.
Year introduced: 2005, 1963-2003
Pyrans
Organic Chemicals
A broad class of substances containing carbon and its derivatives. Many of these chemicals will frequently contain hydrogen with or without oxygen, nitrogen, sulfur, phosphorus, and other elements. They exist in either carbon chain or carbon ring form.
Year introduced: 1998
Ketones
Organic compounds containing a carbonyl group =C=O bonded to two hydrocarbon groups.
Hydrocarbons, Cyclic
Organic compounds composed exclusively of carbon and hydrogen forming a closed ring that may be either alicyclic or aromatic.
Hydrocarbons, Alicyclic
Organic compounds composed exclusively of carbon and hydrogen. Three or more carbon atoms are arranged in a cyclic structure and they possess aliphatic properties.
Hydrocarbons
Organic compounds that primarily contain carbon and hydrogen atoms with the carbon atoms forming a linear or circular structure.
Heterocyclic Compounds, 2-Ring
A class of heterocyclic compounds that include a two-ring fused structure. Both aromatic and non-aromatic ring structures are included in this category.
Heterocyclic Compounds, 1-Ring
Organic compounds that contain a ring structure made up of carbon and one or more additional elements such as nitrogen and oxygen.
Heterocyclic Compounds
Cyclic compounds that include atoms other than carbon in their ring structure.
Flavonoids
A group of phenyl benzopyrans named for having structures like FLAVONES.
Year introduced: 2004(1963)
Cycloparaffins
Alicyclic hydrocarbons in which three or more of the carbon atoms in each molecule are united in a ring structure and each of the ring carbon atoms is joined to two hydrogen atoms or alkyl groups. The simplest members are cyclopropane (C3H6), cyclobutane (C4H8), cyclohexane (C6H12), and derivatives of these such as methylcyclohexane (C6H11CH3). (From Sax, et al., Hawley's Condensed Chemical Dictionary, 11th ed)
Cyclohexanones
Cyclohexane ring substituted by one or more ketones in any position.
Year introduced: 1991(1975)
Cyclohexanes
Six-carbon alicyclic hydrocarbons.
Year introduced: 1975
Chromones
Benzopyrans
Compounds with a core of fused benzo-pyran rings.
Year introduced: 1966
Heterocyclic Compounds, Fused-Ring
Multiple ring heterocyclic compounds containing two or more rings that share two atoms and one bond in common.
Year introduced: 2017