Synthesis of Diverse N-Trifluoromethyl Pyrazoles by Trapping of Transiently-Generated Trifluoromethylhydrazine.

A one-pot synthesis of functionalized N-trifluoromethyl pyrazoles from readily available di-Boc trifluoromethylhydrazine and dialdehydes, diketones, carbonylnitriles, and ketoesters/amides/acids is described. 19F NMR studies were used to characterize the stability of trifluoromethylhydrazine HCl salt in solution and in solid form and identified a short solution-state half-life of ∼6 h. Optimization of cyclization conditions identified DCM, combined with a strong acid, as a key to suppress the undesired des-CF3 side products, which formed as a result of the instability of trifluoromethylhydrazine and related intermediates. Despite the short-lived nature of these transient intermediates, their reactivity could be utilized to directly deliver a diverse array of pharmaceutically relevant N-trifluoromethyl pyrazoles in synthetically useful yields.

Evaluation of lightwand-guided endotracheal intubation for patients with missing or no teeth: a randomized controlled study.

BACKGROUND: Unhealthy teeth can seriously affect general health and increase the risk of death in elderly people. There has been no confirmation of which device is most effective for elderly patients with teeth loss. Therefore, we compared four intubation devices in elderly patients with partial and total tooth loss aiming to reduce risk during anesthesia. METHODS: Two hundred patients were randomized to undergo tracheal intubation with the Macintosh laryngoscope, the Glidescope, the Fiberoptic bronchoscope or the Lightwand as part of general anesthesia. A unified protocol of anesthetic medications was used. HR and BP were measured at T0, T1, T2, T3, T4 and T5. Catecholamine (epinephrine and norepinephrine) blood samples were drawn at T0, T1 and T2. Intubation time and postoperative complications, including dental damage and losses, were recorded. RESULTS: Reduced fluctuations in HR, DBP, and SBP were observed in the Lightwand group. Intubation time was significantly shorter in the Lightwand group (p < 0.05). There was no statistically significant difference between the groups in epinephrine levels, but norepinephrine levels were less volatile in the Fiberoptic bronchoscope and Lightwand groups. Fewer patients in the Lightwand group experienced dental damage and other postoperative complications than in the other three groups. Although a higher success rate on the first attempt was as high as in the Fiberoptic bronchoscope group, shorter intubation time was observed only in the Lightwand group. CONCLUSION: The Lightwand offers less hemodynamic stimulation than the Macintosh laryngoscope, Glidescope, and Fiberoptic bronchoscope. Because it had the shortest intubation time, the Lightwand caused the least damage to the teeth and throat of elderly patients. Our findings showed that tracheal intubation with the Lightwand was advantageous for preventing cardiovascular stress responses with short intubation times and fewer postoperative complications.