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Molecular interactions between drug and polymeric carriers are believed to be the key for high drug loading and better physical stability of micro-particles. However, molecular interactions between drug and polymer are still difficult to investigate using only experimental tools. In this study, high-loaded glipizide (GLP)/hydroxypropyl methylcellulose acetate succinate (HPMCAS) (1/1 w/w) micro-particles were prepared using an in situ pH-dependent solubility method. Molecular interactions within the micro-particles were investigated by integrated experimental and modeling techniques. The dissolution rate of GLP/HPMCAS micro-particles was significantly better than those of solid dispersions and physical mixtures. Scanning electron microscopy images showed that the polymer inhibited GLP recrystallization. Experimental (FTIR spectroscopy, differential scanning calorimetry, powder X-ray diffraction and nuclear magnetic resonance spectroscopy) and molecular dynamics simulation revealed that hydrogen-bonding was the key to the properties of the micro-particles. Our research developed high drug-loading GLP/HPMCAS micro-particles and investigated the interactions between drug and polymer at the molecular level. This integrated approach could be practical methodology for future formulation design.

Psychological resilience reflects the capacity to bounce back from stress, which plays an important role in health and well-being. However, less is known about the neural substrate for psychological resilience and the underlying mechanism for how psychological resilience enhances subjective well-being in the healthy brain. To investigate these issues, we employed fractional amplitude of low-frequency fluctuations (fALFF) measured with resting-state fMRI in 100 young healthy adults. The correlation analysis found that higher psychological resilience was related to lower fALFF in the left orbitofrontal cortex (OFC), which is involved in reward-related processing and emotion regulation. Furthermore, the mediation analysis indicated that psychological resilience acted as a full mediator of the association between the fALFF in left OFC and subjective well-being indicators (i.e. life satisfaction and hedonic balance). Importantly, these results remained significant after controlling for the effect of gray matter volume and regional homogeneity in the region. Overall, the present study provides the further evidence for functional neural substrates of psychological resilience and reveals a potential mechanism that psychological resilience mediates the effect of spontaneous brain activity on subjective well-being.

Ring opening reactions of N-sulfonyl aziridines by primary and secondary amines in silica gel (SG)-water system were achieved, which provided a mild, practical and environmentally benign method to synthesize mono- and bis-sulfonyl substituted amines. When primary and secondary amines were used in excess, they reacted with N-sulfonyl aziridines smoothly at room temperature, mainly affording 1:1 ring opening products. Reactions of primary amines with 2 equiv. of aziridines produced 2:1 ring opening products. Some 1:1 products can be cyclized with CS2 to synthesize N-sulfonyl cyclothioureas also in water.

In this paper, the thermally induced crystallization behavior of N,N,N′,N′-tetraphenylbenzidine (TPB) and N,N,N′,N′-tetra-p-tolylbenzidine (TTB) and their microstructure changes as well as π–π aggregation mode as film state were comprehensively studied. The influence of heating rate, annealing temperature and time on the non-isothermal crystallization behavior of TPB and TTB powder was evaluated by Jeziorny method. Cold crystallization with the transition of metastable state was observed for both TPB and TTB. The thermally induced microstructure alteration and aggregation pattern of TPB and TTB films were investigated using XRD, SEM and AFM. The results revealed that both TPB and TTB could form smooth amorphous thin film and effective π–π interaction with identical edge-on orientations. TTB was prone to pack with both edge-on and face-on orientations especially after annealing, which accounts for its relatively low hole mobility. Besides, a more ordered film microstructure was formed after annealing at 70 °C for 24 h, which results in nearly four times increase of the hole mobility.

N -Sulfonylcyclothioureas were synthesized from N -sulfonyldiamines and CS 2 with moderate to good yields in silica gel-water system. Moreover, the silica gel can be recycled for at least three times.

A sequential one-pot synthesis of N-sulfonylcyclothioureas from N-monosulfonyl diamines, CS2 and chloroacetic acid at room temperature in water is described. In the absence of highly toxic thiophosgene and organic solvents, this method is environmentally benign. Simple reaction conditions, easy purification of the products, good yields and thioglycolic acid as the useful byproduct are also important attributes of this methodology. The plausible mechanism including tandem reactions is proposed.

When primary and secondary amines are used in excess, they react with N-sulfonyl aziridines, mainly affording 1:1 ring opening products (III), (V), (XI).

The reaction is conducted under environmentally benign conditions, avoiding heating, thiophosgene, and organic solvents.

N -Sulfonylcyclothioureas were synthesized from N -sulfonyldiamines and CS 2 with moderate to good yields in silica gel-water system. Moreover, the silica gel can be recycled for at least three times.