The ether dimer of α- hydroxymethyl)acrylic acid showed unexpectedly high cyclization efficiency (intermediate between secondary and tertiary esters) despite having the lowest substituent bulkiness.
However, the compounds of (4a), (4k); (4m), (4o); (4e), (4o) and (4g), (4r) were not showed any activity against S. aureus, streptococcus pyogenes, and B. subtilis, respectively; it may be rational owing to the presence of low polar substituents.
Furthermore, the effect on the surface is unexpectedly observed at any doping depth down to the 7th layer, and a low concentration of substituent boron – only ¼ – is effective for graphene formation.
Polyamides with alicyclic tert-butylcyclohexyl cardo and trifluoromethyl substituents exhibited low dielectric constants ranging from 3.29 to 3.98 (at 100 Hz) compared with commercially available polyamides [Amodel®, 4.2 5.7 at 100 Hz].
For series a, without any ortho substituent, the low-frequency band νOH(2) peaked at 3616 cm−1 irrespective of the nature of the meta substituent.
These structural effects indicate that substituents with low p Ka can facilitate both Pα Olg bond breaking and the Pα Onuc bond forming process, thus explaining the large negative βlg calculated for the transition state geometry that has significantly longer Pα Onuc distance than the Pα Olg distance.
Small aryl substituents result in the formation of low molecular weight oligomers, whereas bulky aryl substituents gave high molecular weight polyethylene.
The transition-state energies for the nucleophilic attack towards the diacetylenic ketone (TS(D′– E′)) were found to be low lying irrespective of the substituents, suggesting reversibility of this elemental step.
The presence of hydrophobic subsituent OCH3 markedly favoured the cellular uptake of pyrazoloacridines and pyrazolopyrimidoacridines while compounds having hydrophilic substituent OH exhibited very low kinetics of cellular uptake.
Iodonium salts bearing electron-withdrawing groups in metaposition (e.g., m-NO2) or an electron-donating substituent (p-OMe) gave low radiochemical yields under the same conditions.
