42839-09-8Relevant articles and documents
Asymmetric zinc porphyrin derivatives bearing three pseudo-pyrimidine: Meso -position substituents and their photosensitization for H2evolution
Zeng, Peng,Zheng, Ya,Chen, Shengtao,Liu, Haoran,Li, Renjie,Peng, Tianyou
, p. 11237 - 11247 (2020/08/21)
Novel asymmetric zinc porphyrin derivatives (ZnPy-5 and ZnPy-6) with meso-positions bearing one benzoic acid and three pseudo-pyrimidines with two N atoms located at different positions were synthesized and utilized as sensitizers for Pt-loaded g-C3N4 (PCN). Compared to the analogue (ZnPy-1 bearing one benzoic acid and three phenyl meso-position substituents), ZnPy-5 and ZnPy-6 exhibit significantly enhanced photosensitization on PCN under visible light (λ ≥ 420 nm) illumination. In particular, ZnPy-5/PCN and ZnPy-6/PCN exhibit H2 evolution activities of 418 and 585 μmol h-1, corresponding to turnover numbers (TON) of 8845 and 12?381 h-1, respectively. Both of these values are much better that (316 μmol h-1) of ZnPy-1/PCN, which has a TON of 6687 h-1. In addition, ZnPy-5/PCN and ZnPy-6/PCN show apparent quantum yields of 32.6% and 33.1% at 420 nm monochromatic light, and these are much higher than that (10.6%) for ZnPy-1/PCN. Compared with ZnPy-5, the two N atoms of the pseudo-pyrimidines in ZnPy-6 are further away from the porphyrin macrocycle, which can more effectively combine with the sacrificial reagent and g-C3N4, thus promoting dye regeneration and the photoexcited charge transfer for delivering better photocatalytic performance. The present results demonstrate that the number and positions of the N atoms in the peripheral substituents of the porphyrin derivatives have a great influence on the photosensitization, and that the fine-tuning of molecular structures is crucial for improving the H2 evolution activity of the dye-sensitized semiconductors.
Peptidomimetic Vinyl Heterocyclic Inhibitors of Cruzain Effect Antitrypanosomal Activity
Chenna, Bala C.,Li, Linfeng,Mellott, Drake M.,Zhai, Xiang,Siqueira-Neto, Jair L.,Calvet Alvarez, Claudia,Bernatchez, Jean A.,Desormeaux, Emily,Alvarez Hernandez, Elizabeth,Gomez, Jana,McKerrow, James H.,Cruz-Reyes, Jorge,Meek, Thomas D.
, p. 3298 - 3316 (2020/04/08)
Cruzain, an essential cysteine protease of the parasitic protozoan, Trypanosoma cruzi, is an important drug target for Chagas disease. We describe here a new series of reversible but time-dependent inhibitors of cruzain, composed of a dipeptide scaffold appended to vinyl heterocycles meant to provide replacements for the irreversible reactive "warheads" of vinyl sulfone inactivators of cruzain. Peptidomimetic vinyl heterocyclic inhibitors (PVHIs) containing Cbz-Phe-Phe/homoPhe scaffolds with vinyl-2-pyrimidine, vinyl-2-pyridine, and vinyl-2-(N-methyl)-pyridine groups conferred reversible, time-dependent inhibition of cruzain (Ki? = 0.1-0.4 μM). These cruzain inhibitors exhibited moderate to excellent selectivity versus human cathepsins B, L, and S and showed no apparent toxicity to human cells but were effective in cell cultures of Trypanosoma brucei brucei (EC50 = 1-15 μM) and eliminated T. cruzi in infected murine cardiomyoblasts (EC50 = 5-8 μM). PVHIs represent a new class of cruzain inhibitors that could progress to viable candidate compounds to treat Chagas disease and human sleeping sickness.
COMPOUNDS AND RELATED COMPOSITIONS AND METHODS OF USE
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Page/Page column 33, (2013/03/26)
Compounds and compositions, which can be use for example, for treating cancer, are described herein.