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A highly efficient approach to the synthesis of a series of pyrimido[b]azepines has been developed with 5-allyl-2,4,6-trichloropyrimidine as the starting material in six or seven steps via a ring-closing metathesis (RCM) reaction. The absolute configuration of the key intermediate pyrimido[4,5-b]azepine was ascertained by X-ray crystal structure analysis.

Avoiding well collision has become an increasingly critical challenge for the drilling industry in recent years. The wellbore Anti-collision Monitoring system is developed because the vibrations caused by an approaching drill bit can be monitored from the existing well casing and used to pre-alarm the wellbore collision. By analyzing the time-domain signal collected by the system in different drilling conditions, the influences of the drilling parameters (RPM and WOB) on drill bit signal are identified; and by analyzing the frequency-domain signal, the characteristic frequency range (200-400Hz) of the drill bit signal is determined. When the drill bit is approaching to the adjacent well, the reconstruction bit signal after band-pass filter changes significantly and agrees well with the on-site situation. The field test results show that the monitoring system is effective and provides a new way to the anti-collision techniques.

A novel 2-pyridinone scaffold was rationally designed and synthesized based on the active anti-HIV agent 1 (LAM-trans) via an efficient method. The biological results revealed that some target compounds inhibited HIV-1 reverse transcriptase in the lower micromolar concentration range (IC50 0.089–0.68 μm). Notably, the most promising compound 25b exhibited extremely potent inhibitory activity against HIV-1 replication with an EC50 value of 0.0563 μM and the viral selectivity index amounted to 3466.8. Molecular modeling studies were performed, and some SARs were rationalized.