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7,8 Dihydroxy 3 methyl isochromanone 4 XJP is a polyphenolic natural product with moderate antihypertensive activity. T o obtain new agents with stronger potency and safer profile , we employed XJP and naftopidil as the lead compound s t o design and synth esize a novel class of hybrids as antihypertensive candidates, In the present study, a series of hybrids ( 6a r ) of XJP bearing arylpiperazine moiety, which is identified as the pharmacophore of naftopidil, were designed and synthesized as novel ? 1 adrenergic receptor antagonists. The biological evaluation showed that target compounds 6c , 6e , 6f , 6g , 6h , 6m and 6q possessed potent in vitro vasodilation potency and ? 1 adrenergic receptor antagonistic activity . Furthermore, the most potent compound 6e significantly reduced the systolic and diastolic blood pressure in spontaneously hypertensive rats (SHRs),which was comparable to that of naftopidil, and it had no observable effects on the basal heart rate, suggesting that 6e deserves to be further investigated as a potential clinical candidate for the treatment of hypertension.

A series of novel 4-isochromanone hybrids bearing N-benzyl pyridinium moiety as dual binding site acetylcholinesterase inhibitors have been designed and synthesized. The screening results showed that most of the compounds exhibited potent anti-AChE activity in the range of nM concentrations. The 1-(4-fluorobenzyl) substituted derivative 9d exhibited the most potent anti-AChE activity with IC50 value of 8.9 nM and high AChE/BuChE selectivity (SI>230). Kinetic and molecular modeling studies suggested that compound 9d was mixed-type inhibitor, binding simultaneously to CAS and PAS of AChE. Besides, the preliminary structure-activity relationships were discussed.

The synthesis of 4-isochromanones via Parham-type cyclization with Weinreb amide as the internal electrophilic group, t-BuLi as the lithium reagent was described. The reaction was efficient and could be completed in one minute. The application scope of this new protocol was investigated and the desired products could be obtained in good to excellent yields. Besides, the synthetic potential of this method was further demonstrated by the synthesis of natural product (±)-XJP, which was obtained in six steps with overall yield up to 54%.

New metal-free organic sensitizers containing a fluorene unit as a π-conjugated system, a diphenylamine as an electron donor, and a cyanoacrylic acid moiety as an electron acceptor were synthesized and used for dye-sensitized solar cells. The photophysical and electrochemical properties of these dyes were investigated, and their performances as sensitizers in solar cells were measured. One solar cell containing the n -hexyl group in the fluorene unit produced an η of 5.15% ( J sc = 9.69 mA cm −2 , V oc = 0.77 V, and ff = 0.70) under 100 mW cm −2 simulated AM 1.5 G solar irradiation (100 mW cm −2 ).

Five kinds of triphenylamine-based organic dyes with different electron acceptors were designed and synthesized as sensitizers for dye-sensitized solar cells (DSSCs). The photophysical and electrochemical properties of these dyes were investigated and their performance as sensitizers in DSSCs was measured. The dye with cyanoacrylic acid electron acceptor exhibits the highest solar-to-electrical energy conversion efficiency of 4.93% (short-circuit photocurrent density J sc = 8.59 mA cm −2 , open-circuit photovoltage V oc = 0.77 V, and fill factor ff = 0.75) under 100 mW cm −2 -simulated AM 1.5 G solar irradiation.

New metal-free organic sensitizers containing a benzo[d]thiazole or phenyl unit as the π-conjugated system, a triphenylamine as an electron donor, and a cyanoacrylic acid moiety as an electron acceptor were synthesized and used for dye-sensitized solar cells. Photophysical and electrochemical properties of these dyes were investigated, and their performances as sensitizers in solar cells were measured. The introduction of a benzo[d]thiazole unit into the molecular structure resulted in a high incident photon-to-current conversion efficiency (more than 70%) from 340 nm to 600 nm. One solar cell containing a benzo[d]thiazole unit, produced a η of 5.85% (JSC = 10.63 mA cm−2, VOC = 0.72 V, and ff = 0.77) under 100 mW cm−2 simulated AM 1.5 G solar irradiation.

Novel polymer gel electrolytes (PGEs) with high ionic conductivity based on polyvinyl (acetate-co-methyl methacrylate) [P(VA-co-MMA)] were prepared by soaking porous copolymers in an organic electrolyte solution [acetonitrile (ACN) or 3-Methoxypropionitrile (MPN)] that contained an I 3 − /I − as redox couple. Quasi-solid-state dye-sensitized solar cells (QS-DSSCs) were fabricated with the PGEs, and the best PGE was selected and optimized. Using the best PGE and under 100 mW cm −2 light illumination (AM1.5), the QS-DSSC achieved a high photovoltaic conversion efficiency of 9.10%, nearly the same as that for the DSSC based on the original liquid electrolyte. Introduction of TiO 2 nanoparticles into the PGEs further enhanced PGEs ionic conductivity and the conversion efficiency to 9.40%. Subsequent results revealed that our QS-DSSC had a better stability because it could maintain 96.7% of its initial efficiency after long-time (1000 h) exposure to simulative sunlight. Besides, for the first time, large-area QS-DSSCs were fabricated by screen printing of PGE, other than the traditional vacuum injection that was infeasible for the viscous gel electrolyte. Finally, our 5 cm × 7 cm QS-DSSC sub-module exhibited a conversion efficiency higher than 4%.

The highly soluble polyvinyl acetate (PVAc) was synthesized by simple solution polymerization, which was used to prepare the gel-state dye-sensitized solar cells (DSCs) for the first time. The values for open-circuit photovoltage (Voc), short-circuit photocurrent density (Jsc), and fill factor (FF) of gel electrolyte-based DSCs were 0.712 V, 16.78 mA cm–2, and 68%, respectively, yielding an overall photovoltaic conversion efficiency (PCE) of 8.18%, which is comparable to a liquid electrolyte-based one with a value of 8.27%. The results of the electrochemical impedance spectra (EIS) revealed that the large charge transfer resistances at the TiO2/dye/electrolyte interface and the large diffusion resistances of the redox couple in the electrolyte are responsible for similar PCEs of gel and liquid electrolytes. The long-term stability test revealed that the PCE of the gel electrolyte-based DSC did not decay after 1000 h under AM1.5 simulated solar illumination at 60 °C and 40–50% humidity, which is superior t...

The synthesis of 4-isochromanones via Parham-type cyclization with Weinreb amide as the internal electrophilic group, t-BuLi as the lithium reagent was described. The reaction was efficient and could be completed in one minute. The application scope of this new protocol was investigated and the desired products could be obtained in good to excellent yields. Besides, the synthetic potential of this method was further demonstrated by the synthesis of natural product (±)-XJP, which was obtained in six steps with overall yield up to 54%.

Low-cost bendable photoanodes and counter electrodes (CEs), as well as gel electrolytes, are potentially desired for the mass production of completely flexible dye-sensitized solar cells (DSSCs). In this work, via printing at low temperature, we fabricated titanium carbide (TiC)-functionalized conductive-carbon (CC) on flexible polyimide (PI) films to replace traditional and expensive Pt/ITO/PEN CEs. Morphology characterization revealed this composite CE was highly porous and homogeneous. Electrochemical investigations demonstrated that this Pt-and-ITO free flexible CE exhibited a high electro-catalytic activity. Finally, the conversion efficiencies of the all flexible quasi-solid DSSCs using this low-cost TiC-CC/PI CE achieved 86% of that based on a Pt/CC/PI CE. Thus, the facile fabrication process of this novel CE, along with its notable performance, are quite promising for the future roll-to-roll production of completely flexible DSSCs.

A series of bis(oxalate)borate ionic liquids (ILBOBs) were developed for the first time as the necessary components of the electrolyte system for dye-sensitized solar cells (DSCs). It was found that the photovoltaic performances of DSCs were significantly improved by 26% to 45% with these ILBOBs in the organic solvent electrolytes. Systematic investigations were carried out to reveal the effects of the chain lengths of the quaternary ammonium BOB as well as the cations of the ILBOBs on the performances of the DSCs. Among them, the highest power conversion efficiency (PCE) was achieved by the DSC based on the electrolyte containing 1-ethyl-3-methylimidazolium bis(oxalate)borate (EmimBOB). Specifically, the addition of EmimBOB increased the short circuit current densities (Jsc) from 11.87 mA cm−2 to 15.99 mA cm−2, and the open-circuit voltage (Voc) from 0.721 V to 0.742 V, accompanied by a final 45% improvement of the overall PCE from 6.01% to 8.73% under AM 1.5, 100 mW cm−2 illumination. As an ionic liquid, EmimBOB was also used to develop a solvent-free electrolyte system. Compared with the one containing pure 1-methyl-3-propylimidazolium iodide (PMII), the hybrid solvent-free electrolyte system based on the EmimBOB/PMII combination notably increased the PCE of the DSCs from 3.48% to 5.38%. Finally, using solvent-free electrolytes, the long-term stability of the DSC devices were remarkably improved.