Terthienyls

Instead of thiophenes the readily available di-2-thienylmethane can be used as a chain extender, introducing a nine carbon unit upon desulfurization. Similarly the two reactive positions of 2,2-bithienyl and 2,2, 5",2"-terthienyl have been utilized for the introduction of eight and twelve carbons, respectively. ... 

X0 to hydroxy compounds. Lower temperatures favor ketone formation and sterically hindered carbonyls, such as 2-thienyl t-butyl ketone, are not reduced. The sensitivity of desulfurization to steric factors is evident by the failure to desulfurize 2,5-di-i-butyl-3-acetylthiophene. The carbonyl groups of both aldehydes and ketones can be protected by acetal formation, as particularly cyclic acetals are stable during desulfurization in methanol at room temperature. " The free aldehydes give primary alcohols on desulfurization. Another method to obtain only keto compounds is to oxidize the mixtures of ketone and secondary alcohol with CrOs after the desulfurization. - Through the desulfurization of 5,5 -diacetyl-2,2, 5, 2"-terthienyl (228), 2,15-hexadecandione (229) has been obtained, which... 

It seems quite obvious that the thiophenes are related to the polyacetylenes which they accompany. This viewpoint has recently been illustrated by the formation of thiophenes from polyacetylenes and hydrogen sulfide under almost biological conditions. In a recent lecture summary, the preparation of terthienyl, junipal, and (241) from 1,4-disubstituted butadiynes and hydrogen sulfide is claimed. A large number of bithienyls have been prepared and their nemato-dicidal activity investigated. All the compounds with strong activity were found to be derivatives of 2,2 -bithienyl. ... 

Zechmeister, L., and J. W. Sease A Blue-fluorescing Compound, Terthienyl,... 

A. L. Terthienyl and Poly-terthienyl Ligands as Redox-Switchable Hemilabile Ligands for Oxidation-State-Dependent Molecular Uptake and Release. J. Am. Chem. Soc. 2001, 123, 2503-2516. 

It soon became apparent that before a chemical agent could be implicated under field conditions, the subtle nature of the allelopathic effect would have to be carefully elucidated. It should be possible to demonstrate the release of the chemical agent into the soil environment and its accumulation to phytotoxic concentrations. An example of this phenomena is the accumulation of the thiophene, a-terthienyl, in the root zone of common marigolds (e r e c t a ) ( ) If knapweed is allelopathic, is the effect present at all stages of plant development or is the effect most evident at the vulnerable seedling stage ... 

Tagetes erecta L. Chou Fu Yong (Marigold) (leaf, flower) Alpha-terthienyl, d-limonene, 1-linalool, tagetone, n-nonyl aldehyde.50 Treat sores and ulcers, cold, conjuctivitis, cough, mastitis, mumps. 

Fig. 1.9. Effects of sesquiterpene lactones on European corn borer, (a) Glutathione levels (b) lipid peroxidation synergistic effects of-terthienyl (c) with sesquiterpene lactones from the Asteraceae on larval mortality. Means followed by the same letter are not significantly different in Tukey s test (P < 0.05).

Guillet, G Harmatha, J., Wadell, T.G., Philogene, B.J. R. and Arnason, J.T. (2000). Synergism between sesquiterpene lactones and alpha-terthienyl. Photochemistry and Photobiology 71 111-115. 

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