Related Experiment Video
Updated: May 26, 2026

Transient Expression in Nicotiana Benthamiana Leaves for Triterpene Production at a Preparative Scale
Published on: August 16, 2018
Anthratectone and naphthotectone, two quinones from bioactive extracts of Tectona grandis
Rodney Lacret1, Rosa M Varela, José M G Molinillo
1Grupo de Alelopatía, Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Cádiz, Campus de Excelencia Internacional Agroalimentario, ceiA3, C/ República Saharaui s/n, 11510, Puerto Real, Cádiz, Spain.
Abstract:
Two new quinones, (an isoprenoid quinone, and a dimeric anthraquinone) named naphthotectone and anthratectone, respectively, were isolated from bioactive leaf extracts from Tectona grandis. Their structures were determined by a combination of 1D and 2D NMR techniques. The bioactivity profile of naphthotectone was assessed using the etiolated wheat coleoptiles bioassay in aqueous solutions at concentrations ranging from 10(-3) to 10(-5)M, as well as the standard target species lettuce, cress, tomato, and onion. Naphthotectone showed high level of activities in both bioassays. This fact, along with the presence of this compound as the major component in Tectona grandis, suggests that it may be involved in the allelopathic activity previously described for this species, and probably in other defense mechanisms.
Related Concept Videos
Oxidation of Phenols to Quinones
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox property is crucial in...
Cholinergic Antagonists: Chemistry and Structure-Activity Relationship
The Electron Transport Chain
Inhibitors of the electron transport chain
Rotenone, a widely used pesticide, prevents electron transfer from Fe-S cluster to ubiquinone or Q in...
Antidotes
Specific antidotes operate by inhibiting the enzymes that control biochemical pathways, reducing the production of harmful metabolites.
An example of an antidote is atropine, which counteracts the detrimental effects of cholinesterase inhibitors. It achieves this by deactivating muscarinic receptors,...
Phase II Reactions: Miscellaneous Conjugation Reactions
A key example involves the conjugation of cyanide ions, which impair cellular respiration and alter hemoglobin into non-oxygen-carrying cyanmethemoglobin. To neutralize this threat, a sulfur atom from thiosulphate is transferred to the cyanide ion, catalyzed by the enzyme rhodanese, resulting in an inactive compound called thiocyanate. The production of...
Indirect-Acting Cholinergic Agonists: Chemistry and Structure-Activity Relationship
Reversible inhibitors display short to medium durations of action. Short-acting agents include simple alcohols with...