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The resorcin[4]arene host compound 2,8,14,20-tetrapentadecylpentadecylpentacyclo [19.3.1.1.(super 3,7)1(super 9,13)1(super 15,19)]octacosa-1 (25),3,5,7(28),9,11,13(27),15,17,19(26),21,23-dodecaene-4,6,10,12,16,18,22,24-octol is shown to form charge-transfer complex with a series of electron acceptors including [60]- and [70]fullerenes.

Both [60]- and[70] fullerences form 1:1 supramolecular complexes with the calixarenes. Calixarene 3 forms a stronger inclusion complex due to preorganization.

Research has been conducted on the metal-arene systems. The use of these systems as organic TiCl (sub)3 reductants has been investigated and the method to create highly reactive low-valent titanium reagents has been developed.

The synthesis three congeners of the commercially available pyrromethene 567 (PM567) laser dye were carried out and their photophysical properties, lasing efficiencies, and photochemical stabilities were studied. The results provide possible future pathways to improve the design of highly efficient PM dye molecules in terms of higher photochemical stability for their application in liquid dye lasers.

A detailed (super 1)H and (super 13)C NMR spectrometric study was carried out to obtain insight into the nature of molecular interactions of the electron donor-acceptor (EDA) complexes of [60]fullerene with series of anisoles, namely, anisole, m-bromoanisole, and p-bromoanisole. The results shows that [60]Fullerene are shown to form 1:1 adducts with the above series of anisoles.

[70]fullerene is shown to form 1:1 supramolecular complexes with various mono O-substituted calix[6] arenes under study. Thermodynamic parameters are determined for the complexes under study, which have shown that a solvophobic effect and pi-pi interactions are major driving forces for the complexation process.

Formation constants (K) of the complexes were determined from the systematic variation of NMR chemical shifts of specific protons of the crown ethers in the presence of [60]fullerene and[70]fullerene. The magnitudes of K indicated that crown ethers dibenzo-24-crown-8 and dibenzo-30-crown-10 form inclusion complexes with [60]fullerene but not [70] fullerene.

Electronic absorption spectroscopy is used for the study of complexes of fullerene C70 with aniline and various substituted anilines in CCl4 medium. It has been observed that C70 acts as a better acceptor than C60 does in forming charge transfer (CT) complexes and the degree of charge transfer in the ground state of the complexes has been found to be very low (0.2--0.3%).

Triazolinediones (TADs) are unique reagents in organic synthesis that have also found wide applications in different research disciplines, in spite of their somewhat "exotic" reputation. In this review, we offer two case studies that demonstrate the possibilities of these versatile and reliable synthetic tools, namely, in the field of polymer science as well as in more recently emerging applications in the field of click chemistry. As the general use of triazolinediones has always been hampered by the limited commercial and synthetic availability of such reagents, we also offer a review of the available TAD reagents, together with a detailed discussion of their synthesis and reactivity. This review thus aims to serve as a practical guide for researchers that are interested in exploiting and further developing the exceptional click-like reactivity of triazolinediones in various applications.

An efficient and chemoselective route for transforming BF2-BODIPYs to Et2B-BODIPYs (masking) was developed using Et2AlCl. The Et groups can be easily replaced with F atoms using BF3·Et2O in moist CH2Cl2 to regenerate the BF2-BODIPYs (demasking). The masking-demasking strategy is very useful for synthesizing functionalized BODIPYs via nucleophilic and reductive reactions. The masking strategy was used to synthesize a BODIPY dimer by McMurry coupling of a formyl Et2B-BODIPY, while a new BODIPY with an asymmetrically substituted B-center was synthesized using the demasking strategy.

Starting from some meso-methyl Bodipy dyes, the corresponding meso-styryl derivatives were synthesized by regioselective Knoevenagel-type condensation with different aromatic aldehydes. The reactions were driven by the alleviation of the structural strain of the alkyl substituted Bodipys that could override the differential acidities of the methyl protons at the pyrrole ring of the Bodipy moiety., (© 2011 American Chemical Society)

Two new C-1 epimeric hydroxymethyl castanospermine congeners 2a and 2b, synthesized by stereocontrolled intramolecular double reductive amination of D-glucose derived beta-keto ester as a key step, showed impressive immuno-potentiating property. The bioactivity was mediated through up-regulation of T(H1)/T(H2) cytokine ratio. The finding suggested that immunmodulatory activity of polyhydroxylated indolizidine alkaloids can be tuned by minor structural/stereochemical alterations.

The 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay of the ethanol extracts of three varieties (Bangla, sweet, and Mysore) of Piper betel (pan) revealed the Bangla variety to possess the best antioxidant activity that can be correlated with the total phenolic content and reducing powers of the respective extracts. Column chromatography of the extract of the Bangla variety led to the isolation of chevibetol (CHV), allylpyrocatechol (APC), and their respective glucosides. The HPTLC analyses of the extracts revealed similar chemical profiles in all three P. betel varieties, although the concentrations of CHV and APC were significantly less in the sweet and Mysore varieties. Among the isolated compounds, APC showed the best results in all the in vitro experiments. It could prevent Fe(II)-induced lipid peroxidation (LPO) of liposomes and rat brain homogenates as well as gamma-ray-induced damage of pBR322 plasmid DNA more efficiently than CHV. The superior anti-LPO and radioprotective activities of APC vis-à-vis those of CHV could not be explained by their respective Fe(II) chelation and .OH radical scavenging capacities. The better ability of APC to scavenge O2-. radicals and H2O2 might account for the results.

The 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay of the ether, methanol, and aqueous extracts of the spice Myristica malabarica (rampatri) revealed the methanol extract to possess the best antioxidant activity. Column chromatography of the methanol extract led to the isolation of a new 2-acylresorcinol and four known diarylnonanoids of which the diarylnonanoid, malabaricone C, showed the maximum DPPH scavenging activity. Malabaricone C could prevent both Fe(II)- and 2,2'-azobis(2-amidinopropane)dihydrochloride-induced lipid peroxidation (LPO) of rat liver mitochondria more efficiently than curcumin. The anti-LPO activity of malabaricone C was attributed to its better radical scavenging and Fe(II) chelation capacities. The superior activity of malabaricone C was rationalized by a systematic structure-activity correlation of the results obtained with the structurally related diarylnonanoids and curcumin. Malabaricone C also prevented the gamma-ray-induced damage of pBR322 plasmid DNA in a concentration-dependent manner. The radioprotective activity was found to correlate with its (*)OH radical scavenging property, which matched well with that of d-mannitol.