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A series of highly tunable bifunctional phosphine-squaramide H-bond donor organocatalysts 6 has been synthesized from inexpensive and commercially available β-amino alcohols in moderate yields. Catalyst 6 f can efficiently promote the asymmetric Morita-Baylis-Hillman (MBH) reaction of N-alkyl isatins with acrylate esters providing the chiral 3-substituted 3-hydroxy-2-oxindoles in good yields and enantioselectivities (up to 93 % yield and 95 % ee), in which the challenging substrate tert-butyl acrylate 9 d, provided the best ee value to date. Moreover, this methodology was applied successfully in the synthesis of chiral cyclic spiropyrrolizidineoxindole and γ-butyrolactone derivatives without enantioselectivity deterioration. The possible mechanism of this MBH reaction was also investigated by 31P NMR, ESI-MS and KIE studies. The KIE experiments show that the electrophilic addition of N-methyl isatin to the complex of acrylate ester and phophine-squaramide is the rate-determing step of the asymmetric MBH reaction. [ABSTRACT FROM AUTHOR]

Objective: To investigate the impact of the restoration of non-bracket invisible orthodontic titanium alloy implant on individuals with dental malocclusion and arch deficiency accompanied by periodontitis and local periodontal Inflammation., Method: A cohort of 120 patients presenting with dental malocclusion and defects compounded by periodontitis, were treated at our institution between January 2021 and January 2022; these patients were enrolled in a randomized controlled trial.. These patients were allocated into two groups. The control group (comprising 60 cases) underwent titanium alloy implant restoration, while the research group (also with 60 cases) received titanium alloy implant restoration following invisible orthodontic treatment without brackets. A one-year post-treatment follow-up was conducted, during which various parameters, including pain levels, aesthetic improvement, inflammatory response, dental function, oral hygiene, and the incidence of adverse events, were evaluated and compared before and after treatment between the two groups., Results: After six months of treatment, the visual analog scale (VAS) in the study group was lower than that in the control group (P < .05). After 6 months of treatment, the research team observed the changes in gingival crevicular interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), Interleuckin-1 (IL-1), plaque index (PLI), and soft dirt index (DI) were all lower than those in the control group (P < .05). After 6 months of treatment, the research group had higher scores for tooth functions such as chewing, swallowing, speech expression, and occlusion than the control group, as well as higher pink and white aesthetics indexes (P < .05). The difference in the incidence rate of adverse outcomes between the research and control group was not distinct (P > .05)., Conclusion: In case of dental malocclusion accompanied by periodontal disease, the utilization of titanium implants for rectifying dental arch deformities without the use of orthodontic brackets, devoid of orthodontic brackets, has demonstrated notable efficacy in alleviating patients' periodontal discomfort, their oral hygiene, and dental functionality. This modality is conducive to augmenting dental aesthetics without incurring heightened rates of unfavorable consequences, thereby enhancing treatment outcomes.

Nicotinamide N -methyltransferase (NNMT) catalyzes the methylation of nicotinamide to form N -methylnicotinamide. Overexpression of NNMT is associated with a variety of diseases, including a number of cancers and metabolic disorders, suggesting a role for NNMT as a potential therapeutic target. By structural modification of a lead NNMT inhibitor previously developed in our group, we prepared a diverse library of inhibitors to probe the different regions of the enzyme's active site. This investigation revealed that incorporation of a naphthalene moiety, intended to bind the hydrophobic nicotinamide binding pocket via π-π stacking interactions, significantly increases the activity of bisubstrate-like NNMT inhibitors (half-maximal inhibitory concentration 1.41 μM). These findings are further supported by isothermal titration calorimetry binding assays as well as modeling studies. The most active NNMT inhibitor identified in the present study demonstrated a dose-dependent inhibitory effect on the cell proliferation of the HSC-2 human oral cancer cell line.