Odorless Isocyanide Chemistry: One-Pot Synthesis of Heterocycles via the Passerini and Postmodification Tandem Reaction Based on the in Situ Capture of Isocyanides.

This paper reports the tandem reaction strategy of the Passerini/Staudinger/aza-Wittig reaction based on the in situ capture of isocyanides. According to this strategy, isocyanides are synthesized in situ and immediately work as the substrate for the Passerini reaction and postmodification tandem reaction in one pot. In addition, two types of new compounds, 5-oxo-3,5-dihydrobenzo[ e][1,4]oxazepines and 6-oxo-5,6-dihydro-2 H-1,4-oxazines, were synthesized using the tandem reaction strategy that includes five-step transformations in one pot.

Clinical Efficacy of Epidural Injections of Local Anesthetic Alone or Combined with Steroid for Neck Pain: A Systematic Review and Meta-Analysis.

Aims: To compare the effectiveness of cervical epidural injections of local anesthetic with vs. without a steroid. Methods: Three databases (PubMed, Embase, and Cochrane library) were used to search and assess all clinical randomized controlled trials regarding the clinical efficacy of epidural injections from January 01, 2009, to October 31, 2020. Cochrane review criteria and the Interventional Pain Management Techniques-Quality Appraisal of Reliability and Risk of Bias Assessment instrument were used to evaluate the methodologic quality of the included studies. Qualitative and quantitative analyses were performed according to best evidence synthesis principles and by single-arm meta-analysis, respectively. Results: Based on the search criteria, 4 RCTs were qualitatively and quantitatively analyzed in the single-arm meta-analysis. Treatment with lidocaine alone or with the steroid resulted in decreases of 4.46 and 4.29 points, respectively, in pain scores and of 15.8 and 14.46 points, respectively, in functional scores at 6 months. Similar trends were observed at the 1-year follow-up: pain scores decreased by 4.27 and 4.14 points, while functional scores decreased by 15.94 and 14.44 points in patients with neck pain who received lidocaine without or with the steroid, respectively. In the 3 studies that reported 2-year follow-up data, patients with neck pain treated with lidocaine or lidocaine + steroid showed 4.2- and 4.14-point decreases, in pain score and 15.92- and 14.89-point decreases, respectively, in functional scores. Conclusions: The studies showed level I (strong) evidence for short- and long-term improvements in pain relief and functionality with cervical epidural injections of local anesthetic alone or with a steroid in the management of neck pain.

Efficient regioselective synthesis of indole N-carboximidamides and N-carboximidoates by a sequential Aza-Wittig/Ag(I)-catalyzed cyclization.

An efficient Ag(I)-catalyzed regioselective cyclization of (2-alkynylphenyl)guanidine or (2-alkynylphenyl)isourea to indole N-carboximidamides or N-carboximidoates has been developed. The approach has the advantages of high regioselectivity, mild reaction conditions, easily accessible starting materials, and good yields.

Diethyl 3-amino-4-[(triphenyl-phosphor-anyl-idene)amino]thieno[2,3-b]thio-phene-2,5-dicarboxyl-ate.

The asymmetric unit of the title compound, C(30)H(27)N(2)O(4)PS(2), consists of two crystallographically independent mol-ecules. The thieno[2,3-b]thio-phene ring systems are planar. One of the terminal ethyl groups is disordered over two positions; the site occupancy factors are ca 0.7 and 0.3. The crystal structure is stabilized by N-H⋯N, N-H⋯O and C-H⋯O hydrogen bonds.

3-(4-Chloro-phen-yl)-2-(diisopropyl-amino)-1-benzofuro[3,2-d]pyrimidin-4(3H)-one.

In the mol-ecule of the title compound, C(22)H(22)ClN(3)O(2), the three fused rings of the benzofuro[3,2-d]pyrimidine system are almost coplanar. This ring system is oriented with respect to the substituted benzene ring at a dihedral angle of 79.05 (3)°. Intra-molecular C-H⋯N hydrogen bonding results in the formation of a six-membered ring. In the crystal structure, π-π stacking inter-actions involving the furan, pyrimidinone and benzene rings are present [centroid-to-centroid distances in the range 3.258 (1)-3.870 (1) Å].

[Treatment of petrochemical secondary effluent by ozone-biological aerated filter].

The advanced treatment of petrochemical secondary wastewater by ozone- aerated biological filter was carried out in this study. The effect of pH on ozonation and the removal of COD and UV254 by the ozone-aerated biological filter combined process were investigated. In addition, the variation of relative molecular mass distribution of organics and the characteristics of three-dimensional fluorescence spectra of the wastewater were also investigated. The results showed that the suitable operating conditions of the ozonation unit were: ozone dosage 10 mg x L(-1), contact time 4 min and slightly alkaline pH. Ozonation can transfer macromolecular organics into small molecular organics, resulting in a 15% increase in the percentage of the organics with small relative molecular mass (less than 1 000). The biodegradability of the petrochemical secondary effluent was significantly improved by ozonation, making it more suitable for the treatment by aerated biological filter. The removal efficiency of COD and UV254 were 40.8% and 45.8% when the hydraulic retention time was 3 hours and the gas to water ratio was 3:1 for BAF. The average COD of the petrochemical wastewater was 86.5 mg x L(-1) while the average COD of the effluent of the combined process was 49.4 mg x L(-1) when it was operated under optimal conditions.