Resmi Raghunandan

Vapor-Phase Processable Novel Nonplanar Donor−Acceptor Quateraryls for Blue OLEDs#

A novel series of thermally stable blue light emitting quateraryls with a piperidine donor and a nitrile acceptor was prepared from a ketene- S, S-acetal under mild conditions without using an organometal catalyst. The performance of a blue quateraryl 6e was investigated by fabricating a multilayer OLED with a configuration of ITO/PEDOT:PSS (40 nm)/quateraryl (60 nm)/BCP (6 nm)/Alq(3) (20 nm)/LiF (0.5 nm)/Al (200 nm), which exhibited blue emission with a low turn on voltage of 4 V at a brightness of 0.22 cd/m(2).

Role of arene interactions and substituent effects in conformational (syn/anti) control of 1,2-diarylethanes

Conformational analysis of nine designed flexible 1,2-diarylethanes with different substituents show syn conformation due to π–π interactions by 1H NMR in solution, this carries over to the solid state for three compounds while two show anti conformation in the solid state by X-ray crystallography and the remaining compounds do not give diffraction quality crystals.

Amide Derivatives of 2,3-diarylacrylophenone as Estrogen Receptor Binding Ligands

Substituted amidoalkyl derivatives of 2,3-diarylacrylophenones carrying the amide chain on the 3-aryl residue have been prepared by reacting corresponding phenolic 2,3-diarylacrylophenones with haloalkyl carboxylic acid esters, their hydrolysis and subsequent treatment with different alkyl amines. Compounds thus prepared were evaluated for their relative binding affinity (RBA) towards estrogen receptors (ER), estrogen agonistic and antagonistic activities. Out of eleven amide derivatives thus prepared, compounds 7, 13, 15-19, 23, 24 showed significant estrogen antagonistic activity. Interestingly the phenolic compound 7 and the acid ester 18 also exhibited estrogen inhibiting property. Majority of the dimethoxy derivatives (R = OCH(3)) showed significantly high estrogenic activity. In order to throw light on their SAR, In silico docking of the acrylophenone derivatives in the ligand binding site of the ERalpha and their comparison with pure steroidal estrogen antagonist ICI-164,384 and the non-steroidal antiestrogen raloxifene, was carried out. Crystal structure of compound 6 revealed relative trans-geometry of the 2(B) and 3(C) phenyl rings.

Synthesis of 3-phenyl-4-phenylvinyl Benzopyranones and the Corresponding 2,2-dimethyl-benzopyrans with Structural Similarity to Estradiol, as Estrogen Receptor Ligands

7-Methoxy-3-phenyl-4-phenylvinyl benzopyran-2-ones and the corresponding 2,2-dimethyl-benzopyrans, substituted with different alkylamino residues were synthesized. Except compound 13e, all compounds showed high level of estrogen agonistic activity (>81 %) whereas, compounds 13 b-e and 15a showed significant estrogen antagonistic activity (>20 %). X-Ray analysis of a 7-methoxy-3-phenyl-4-phenylvinyl benzopyran-2-one derivative 13d showed its structural resemblance to endogenous estrogen, 17beta-estradiol. Estrogenic and antiestrogenic activities of these derivatives demonstrate their estrogen receptor (ER) binding ability. The lack of hydroxyl groups at appropriate positions resulted in poor Relative Binding Affinity (RBA).

Bicyclic ketone mediated synthesis of oxygenated aromatic systems

A concise and efficient synthesis of various oxygenated, polycyclic aromatic systems has been delineated through base catalyzed ring transformation of 2-oxo-4-(piperidin-1-yl)-5,6-dihydro-2H-benzo[h]chromene-3-carbonitriles by bicyclic ketones, as a source of carbanions in excellent yields.

Naphtho[2,1- h ]isoquinolines: a new class of partially reduced polycyclic aromatic nucleus

An efficient de novo synthesis of partially reduced naphtho[2,1-h]isoquinolines has been developed through base catalyzed ring transformation of 2-oxo-4-sec-amino-5,6-dihydro-2H-benzo[h]chromene-3-carbonitriles by a carbanion, generated in situ from 1-substituted-4-piperidones in DMF and powdered KOH, in excellent yields. The effect of nitrogen insertion in the D ring of partially reduced benzo[c]phenanthrene on conformational changes has also been studied by X-ray diffraction analysis.