In this study, the persistence of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) was observed in feces, urine and water. In addition, the inactivation of SARS-CoV in wastewater with sodium hypochlorite and chlorine dioxide was also studied. In vitro experiments demonstrated that the virus could only persist for 2 days in hospital wastewater, domestic sewage and dechlorinated tap water, while 3 days in feces, 14 days in PBS and 17 days in urine at 20 degrees C. However, at 4 degrees C, the SARS-CoV could persist for 14 days in wastewater and at least 17 days in feces or urine. SARS-CoV is more susceptible to disinfectants than Escherichia coli and f2 phage. Free chlorine was found to inactivate SARS-CoV better than chlorine dioxide. Free residue chlorine over 0.5 mg/L for chlorine or 2.19 mg/L for chlorine dioxide in wastewater ensures complete inactivation of SARS-CoV while it does not inactivate completely E. coli and f2 phage.

Porphyrin and their analogues usually have a stable aromatic (4n + 2) π-electron system. Porphyrin itself shows aromatic behavior with an 18 π-electron main conjugation pathway in the molecule and has been intensively investigated. 1 However, porphyrin derivatives with 4n π-electron delocation pathways have been little explored owing to their synthetic difficulty, 2,3 and the majority of them are expanded porphyrins 3 because the difference between resonance stabilization energies of 4n and (4n + 2) π-electron systems decreases for larger values of n. 4 To the best of our knowledge, the synthesis of 20 π-electron N,N′-dihydroporphryin (isophlorin) B, referred to for the first time by Woodward during the synthesis of chlorophyll about half a century ago, 5 has represented a challenge for porphyrin chemistry and remained elusive thus far because of its intensive tendency to undergo a twoelectron oxidation and deprotonation to form its corresponding 18 π-electron aromatic porphyrin A.(Scheme 1) Herein, we report the isolation and structural characterization of the 20 π-electron nonaromatic isophlorin 2 and its N-methylation reactions.During our ongoing efforts in synthesis and application of perfluoroalkylated porphyrins, 6 a facile and effective synthesis of the isophlorin 2 was achieved with the accidental discovery of a ready reduction of Cu(II) -tetrakis(trifluoromethyl)-meso-tetraphenylporphyrin (Cu1). 7 When adding activated zinc powder into a DMSO solution of Cu1 at room temperature under nitrogen, the color of the contents changed form green to brown after 1 h. TLC indicated almost complete consumption of the starting porphyrin and formation of a main orange product 2. (Scheme 2) It was relatively air stable 8 to be successfully isolated and thoroughly characterized, although being easily reoxidated to free-base -tetrakis(trifluoromethyl)-meso-tetraphenylporphyrin (H 2 1) with 2,6-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ).X-ray crystal diffraction analysis of 2 ( Figure 1) elucidated that it was a 20 π-electron isophlorin with a highly distorted skeleton that displays a nonplanar saddle conformation. 9 The average displacement for the -carbons from the least-squares plane of the meso-carbon atoms, which can be used to evaluate the magnitude of distortion in the macrocycle, was 1.36 Å for 2 in contrast with 0.89 Å for Cu1. 8 It is also a manifestation of serious distortion of the macrocycle that the pyrrole rings with trifluoromethyl groups and pyrroline rings without trifluoromethyl groups are titled on average by 69.7°and 33.5°, respectively, out of the least-squares plane. The remarkably strong twisting of the pyrrole units might be attributed to considerable steric congestion present between meso and substituents, as well as NH-hydrogen atoms. In addition, an expected feature exhibited in the structure of 2 is that clear C-C bond-length alternation is observed around the macrocycle periphery, which dramatically contrasts with its corresponding 18 π-electron aromatic porphyrin Cu1. 8 Spectroscopic data ...

Agonism of insect odorant receptor (OR) cation channels may represent a new strategy for the manipulation of destructive insect olfactory-driven behaviors. We have explored the chemical space around VUAA1, the first in class agonist of the obligate OR co-receptor ion channel (Orco), and describe novel compound analogues with increased potency across insect taxa. Functional analyses reveal several of these VUAA1 structural analogues display significantly greater potency as compared to the activity of the previously described active compounds in mobility-based behavioral assays on mosquito larvae.