The use of calixarenes in asymmetric catalysis is receiving increasing attention due to their tunable three-dimensional molecular platforms along with their easy syntheses and versatile modification at the upper and lower rims. This review summarizes the recent progress of synthesis and use of chiral calixarenes in asymmetric syntheses which emerged later than 2010.

The clinical impact and accessibility of 99mTc tracers for cancer diagnosis would be greatly enhanced by the availability of a new, simple, and easy labeling process and radiopharmaceuticals. 5‐Fluorouracil is an antitumor drug, which has played an important role for the treatment of breast carcinoma. In the present study, a new derivative of 5‐Fluorouracil was synthesized as (1‐[{1′‐(1′′‐deoxy‐2′′,3′′:4′′,5′′‐di‐O‐isopropylidene‐β‐D‐fructopyranose‐1′′‐yl)‐1′H‐1′,2′, 3′‐triazol‐4′‐yl}methyl]‐5‐fluorouracil) (E) and radiolabeled with 99mTc. It was analyzed by radio thin layer chromatography for quality control and stability. The radiolabeled complex was subjected to in vitro cell‐binding studies to determine healthy and cancer cell affinity using HaCaT and MCF‐7 cells, respectively. In addition, in vitro cytotoxicity studies of compound E were performed with HaCaT and MCF‐5 cells. The radiochemical purity of the [99mTc]TcE was found to be higher than 90% at room temperature up to 6 hours. The radiolabeled complex showed higher specific binding to MCF‐7 cells than HaCaT cells. IC50 values of E were found 31.5 ± 3.4 μM and 20.7 ± 2.77 μM for MCF‐7 and HaCaT cells, respectively. The results demonstrated the potential of a new radiolabeled E with 99mTc has selective for breast cancer cells.

No abstract

No abstract

Herein, a novel calix[4]arene compound, which was modified by the 2‐(2‐aminophenyl)benzothiazole fragment with cyanate recognition function was designed based on the reporter‐spacer‐receptor sensing system. The construction was done via two‐step reaction, and the desired sensor 4 was characterized by FT‐IR, 1H‐, 13C‐NMR, and fluorescence spectroscopy along with HRMS data. The sensor candidate showed distinct fluorometric cyanate detection by means of reporter feature of selected benzothiazole constituent. In the presence of cyanate, the sensor gave a turn‐on‐type fluorescence at 482 nm with a large stokes' shift. Furthermore, it was observed that our fluoroionophore 4 is highly selective toward cyanate over remaining anions such as sulfate, phosphate, fluoride, chloride, bromide, iodide, chlorate, and nitrate in 10% aqueous solution of DMSO. The 1:2 stoichiometric ratio of the 4‐cyanate complex was given the best fit with Job's plot based on the titration data. The association constant (Ka) of sensor 4 with cyanate is determined to be 1.64 × 105 M−2. The obtained limit of detection (LOD) value for cyanate anion, 312 nM, clearly revealed the remarkable sensitivity of the chemosensor 4. This supramolecular method provides a highly adaptive technique for the detection of cyanate and so cyanide ions by current international standard methods.

No abstract

Hydrogen bonding and π-π interactions take special part in the enantioselectivity task. In this regard, because of having both hydrogen acceptor and hydrogen donor groups, melamine derivatives become more of an issue for enantioselectivity. In the light of such information, triazine-based chiral, fluorescence active novel thiazole derivatives L1 and L2 were designed and synthesized from (S)-(-)-2-amino-1-butanol and (1S,2R)-(+)-2-amino-1,2-diphenylethanol. The structural establishment of these compounds was made by spectroscopic methods such as FTIR, H, and C NMR. While the solution of these compounds in DMSO did not show any fluorescence emission, it was observed that the emission increased 44-fold for L1 and 55-fold for L2 in 95% water, similar to the aggregation-induced emission (AIE) characterized compounds. In this regard, enantioselective capabilities of these compounds against carboxylic acids were tested, and in experiments carried out at a ratio of 40/60 DMSO/H O, it was determined that R-2ClMA increased the fluorescence emission of L1 chiral receptor by 2.59 times compared to S-isomer.

The volatile composition of 10 endemic Cephalaria (Dipsacaceae) species (Cephalaria gazipashensis, Cephalaria lycica, Cephalaria paphlagonica, Cephalaria elmaliensis, Cephalaria stellipilis, Cephalaria scoparia, Cephalaria isaurica, Cephalaria cilicica, Cephalaria elazigensis var. purpurea and Cephalaria davisiana) was investigated. The essential oil mixtures were obtained by steam distillation in a Clevenger-type apparatus. Twenty-eight components were identified by GC-FID and GC-MS techniques. While total volatile percentages ranged from 68.99% to 84.57%, the total essential oil yields ranged between 38.15% and 64.05%. Geraniol, α-cedrene and p-cymene were determined as the main components. Geraniol was detected as a major component in C. cilicica (14.64%), and α-cedrene was detected as a major component with 26.03% for C. lycica, 16.93% for C. scoparia, 13.01% for C. davisiana and 10.94% for C. paphlagonica. Cephalaria scoparia, C. davisiana and C. gazipashensis have considerable amount of p-cymene as 12.86%, 12.70% and 11.16%, respectively. This was the first essential oil report concerning the Cephalaria genus.