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The present work describes the s‐trichlorotriazine (TCT)‐mediated formation of highly functionalized ester‐based drugs, namely nafamostat mesylate and camostat mesylate. The TCT‐mediated activation of acids followed by the attack of a hydroxyl group (−OH group) resulted in the formation of ester. The high aqueous solubility of cyanuric acid eases the work‐up process and avoids repetitive washing process (better E‐factor). The present method also avoids using pyridine as a base, and instead of that, N‐methylmorpholine (NMM) was used for the coupling. Moreover, we have also demonstrated the synthesis of key intermediates namely, 4‐guanidinobenzoic acid and 6‐hydroxy‐2‐naphthimidamide from economical and readily available raw materials. The TCT‐mediated coupling provides many advantages in scalability, cost‐effectiveness and environmental friendly handling. [ABSTRACT FROM AUTHOR]

In this paper, we studied the effect of increasing the conjugation in compound 3 on the proton transfer and aggregation‐induced emission properties. Compound 3 exhibited the dual absorption peak at 420 nm and 320 nm, which was redshifted by 50 nm compared to compound 2 (previous report). Compound 3 emits exhibited a peak at 530 nm with a Stokes' shift of 110 nm after photoexcitation at 420 nm. In a high polarity medium, the absorption and emission spectra of compound 3 showed redshifts of 50 nm and 20 nm, respectively. Further, compound 3 displayed the aggregation‐induced emission enhancement in THF/H2O (60 % v/v). Additionally, the proton transfer process in compounds 2 and 3 was evaluated through theoretical calculations via determining the relative free energies of possible tautomeric forms. It was determined that the small energy barriers for compound 2 in the S1 state suggested the presence of the proton transfer process; however, high energy barriers and high stabilization and Boltzmann population of 3.KK tautomeric form at S0 and S1 state for compound 3 discommoded the proton transfer process. Further, the aggregated form of compound 3 (20 μM; CH3OH/HEPES buffer (4 : 1; v/v) pH=7.04) was utilized to recognize Cu2+ ions with the lowest detection limit of 1.5 nM and Stern‐Volmer binding constant of 2.8×105 M−1. A noted decrease in the hydrodynamic size of compound 3 from 400 nm to 40 nm in the presence of Cu2+ ions confirmed the disaggregation with a decrease in emission intensity. Compound 3 was also employed as a Cu2+ ions recognizer in different collected samples with good percentage recovery. [ABSTRACT FROM AUTHOR]

Abstract: In this article, we present fabrication of ecofriendly, biodegradable and printable polyester films using polyethylene glycol, lactic acid and maleic anhydride as monomers. The susceptibility of polyester films towards biodegradation was tuned by varying lactic acid concentration. Films with 0.5 moles concentration of lactic acid exhibited maximum susceptibility towards degradation i. e. 39% in 60 days. Experimental results revealed that the films were printable with ink, label and stamp printing. The films were durable for tape and solvent test and capable of retaining dye on their surface owing to polar interactions between dye molecules and carboxylic groups of polymer chain ends. [ABSTRACT FROM AUTHOR]