Benzoselenadiazole-Functionalized H-bonded Arylamide Foldamers: Solvent-Responsive Properties and Helix Self-Assembly Directed by Chalcogen Bonding in Solid State.

In this study, a series of H-bonded arylamide foldamers bearing benzoselenadiazole ends with solvent-responsive properties have been synthesized. In dichloromethane or dimethyl sulfoxide solvents, the molecules exhibit meniscus or linear structures, respectively, which can be attributed to the unique intramolecular hydrogen bonding behavior evidenced by 1D 1H NMR and 2D NOESY spectra. UV-vis spectroscopy experiments show that the absorption wavelength of H-bonded arylamide foldamers are significantly red-shifted due to the presence of benzoselenadiazole group. In addition, the crystal structures reveal that effective intermolecular dual Se···N interactions between benzoselenadiazole groups induce further assembly of the monomers. Remarkably, supramolecular linear and double helices structures are constructed under the synergistic induction of intramolecular hydrogen bonding and intermolecular chalcogen bonding. Additionally, 2D DOSY diffusion spectra and theoretical modelling based on density functional theory (DFT) are performed to explore the persistence of intermolecular Se···N interactions beyond the crystalline state.

Purification and identification of an actinomycin D analogue from actinomycetes associated with Ganoderma applanatum via magnetic molecularly imprinted polymers and tandem mass spectrometry.

Actinomycetes are main producers of antibiotics and targeted screening could improve the efficiency of discovering new drugs. This study describes, for the first time, the isolation of endophytic actinomycetes from the macrofungus Ganoderma applanatum. To increase the efficiency of screening, novel actinomycin D (Act D) molecularly-imprinted polymers were adsorbed to the surface of Fe3O4@SiO2 magnetic microspheres (MMIPs) and using in the isolation. A monolithic column prepared with magnetic molecularly imprinted polymers was employed to adsorb actinomycin D and its analogues for selective analysis and identification via MS/MS spectroscopy. The MMIP-monolithic column was selective for the structural features of Act D and its analogue, and the maximum loading of the MMIPs for Act D was ∼23.5 µg/g. The recognition time of the Act D was 20-30 min and had good discriminative ability. A new analogue was identified from endophytic actinomycetes KLBMP 2541, and it was purified using MMIPs comparison with MMIPs-solid phase extraction. Structural identification analysis confirmed that the new analogue was 2-methyl-actinomycin D, which has better anti-tumor activity than Act D. The presented method combines the advantages of MMIPs and MS with popular solutions to enable high affinity and selectivity screening of specific antibiotics from endophytic actinomycetes.

[Subarea ostectomy of mandible for lower face re-shaping].

OBJECTIVE: Dividing the mandible into lower part of mandibular ramus, mandibular angle, mandibular body, chin, we designed subarea ostectomy for reduce the width of anterior, body, posterior part of of the lower face. METHODS: Combide with splitting ostectomy of the out layer of mandible, ostectomy of inferior border of mandible and augmentation of the chin, re-shape the mandibular angle, body, and chin, corrected the un-beauty of the lower face and side-face. RESULTS: From May 2003 to August 2005 , a total of twenty-three patients have been operated on by this method with satisfactory results. CONCLUSIONS: Subarea ostectomy of mandible is more effective in re-shaping the whole lower face.

[Improvement of reduction of prominent malar complex through an intraoral incision].

OBJECTIVE: To improve the technique of prominent malar complex reduction. METHODS: The improvements of the operation procedure included double-oblique osteotomy of the prominent malar complex, accessorial tiny preauricular incision and the way that the complex was moved upward, inward or posteriorly. The zygomatic body was fixed with microplate screw or steelwire. The jugal soft tissue was lifted to prevent facial slack. The method was used in 17 cases from June 2000 to April 2004. RESULTS: Postoperative follow up for 4 approximately 24 months showed satisfactory result in all the cases. CONCLUSIONS: This modified method resolved some problems in reduction malarplasty through an intraoral approach.