Conceptualization and Synthesis of the First Inosito-Inositol (Decahydroxydecalin,DHD): In silico Binding to β-Amyloid Protein

Previously unknown entities in the form of 1,2,3,4,5,6,7,8,9,10-decahydroxydecalins (DHDs) have been conceptualized and the first member of this class, an inosito-inositol, has been synthesized from aromatic hydrocarbon naphthalene following a flexible strategy that is amenable to diversity creation. The DHD accessed here has been subjected to preliminary in silico evaluation with Aβ and may hold some promise in Alzheimer's disease therapeutics.     

Influence of β-cyclodextrin complexation on photochemistry of bisphenols in aqueous solutions

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碱金属盐催化1,2,4-三唑与α,β-不饱和酮及二酰亚胺的氮杂Michael反应

发展了一种高效的碱金属盐催化1,2,4-三唑与α,β-不饱和酮及α,β-不饱和二酰亚胺的氮杂Michael加成反应的新方法,以中等到优异的产率得到目标产物.该方法原料易得,底物普适性好,反应条件温和,易实现克级规模的制备.产物容易转化为相应的γ-氨基醇.     

A new erythrinan N-oxide alkaloid from Erythrina stricta

This phytochemical study of stems and leaves of Erythrina stricta led to the isolation of twenty-three alkaloids, one of them previously unreported, 11β-hydroxyerythratidine N-oxide. Their structures were elucidated on the basis of extensive 1D and 2D NMR spectroscopic analyses including HSQC, HMBC, ¹H–¹H COSY, NOESY, as well as HRESIMS data in addition to comparison with reports in the literature.     

柚皮素/β-环糊精超分子体系的包合行为

本文采用超声法制备了柚皮素（NAR）与β-环糊精（βCD）的包合物.粉末-X射线衍射（XRD）和红外吸收光谱（IR）测定均表明形成的包合物具有不同于主客体的新的结构性质.¹H NMR与ROESY核磁共振（NMR）实验表明NAR以苯环端从βCD的宽口端进入，并形成稳定的超分子包合物.量子化学计算分析NAR/βCD包合物的形成过程表明，驱动力源于焓驱动与氢键弱相互作用力；能隙和结合能分析得到的最优包合模式与NMR研究结果一致；ONIOM分层计算验证了上述结果.分子对接模拟出的最优包合模式也与量子化学计算、NMR的分析结果吻合.本文获取了清晰的NAR/βCD包合物构型及其形成机理，为该超分子药物的定量构效关系研究提供了理论参考.     

A facile and efficient method for synthesis of β-iodocarboxylates from terminal epoxides

A facile and efficient method has been developed for synthesis of β-iodocarboxylates in the presences of Ph₃P/I₂. Starting from epoxides, a series of β-iodocarboxylate compounds can be directly obtained in toluene media with excellent yields. Moreover, the method was successfully applied for the late-stage modification of natural products, such as isosteviol and vincamine derivatives, achieving the corresponding β-iodocarboxylates in good yields.     

Transition-metal,organic solvent and base free α-hydroxylation of β-keto esters and β-keto amides with peroxides in water

Without employing any transition metal, organic solvent and base, a facile, economical and environmentally friendly strategy has been developed for the α-hydroxylation of β-keto esters and β-keto amides with peroxides via radical cross-coupling reaction in water under open-air conditions. This protocol allows a convenient access to various α-hydroxy-β-keto esters and α-hydroxy-β-keto amides with up to 92% yield (34 examples). Moreover, the reaction was successfully scaled up to gram quantity and mechanistic studies showed the radical pathway was involved in this hydroxylation.     

Circularly Polarized Luminescence and Circular Dichroism of Bichromophoric Difluoroboron-β-diketonates: Inversion and Enhanced Chirality Based on Spatial Arrangements and Self-Assembly

We synthesized two bichromophoric difluoroboron-β-diketonates (DFB) connected in para and meta positions by using cyclohexane diamine as a chiral bridge ( para and meta (R/S)-CyDFB ). TD-DFT calculations revealed that the variation in connectivity of the DFB units leads to different spatial arrangements and a chirality inversion of the bichromophoric DFB. Higher g_abs values were obtained in (R/S)-CyDFB connected in para as compared to meta position. Aggregation of para (R/S)-CyDFB in mixture of solvents increase the g_lum values as compared to its monomeric form. Ultrasonication and heating induced the formation of highly ordered nano-helical wires of para (R/S)-CyDFB that increased the g_lum values to 0.015. On the other hand, meta (R/S)-CyDFB failed to form highly ordered self-assembled wires due to hindered H-binding sites. These observations indicate that the chiroptical properties of DFB bi-chromophore system can be modulated with self-assembly and spatial arrangement of the chromophores.     

Transition-metal free synthesis of diaryl vinyl selenides: a simple synthetic approach with high selectivity

A simple, highly efficient synthetic protocol is developed for the synthesis of unsymmetrical diaryl vinyl selenides from diaryldiselenide and β-bromo styrene under transition-metal free conditions in N,N′-dimethyl propylene urea and 130 °C to afford high yields and excellent selectivities. This method provides a new strategy to fabricate a wide variety of important substituted molecular skeletons and an alternative to conventionally used metal salts, additives, and ligands.     

Chemical composition and antioxidant activity of essential oil from aerial parts of Teucrium flavum L. subsp. flavum growing spontaneously in Tunisia

The objectives of this study were to chemically characterise and evaluate the antioxidant potential of the essential oil from Teucrium flavum L. subsp. flavum growing spontaneously in Tunisia. The volatile oil was extracted by hydrodistillation of the aerial parts in a Clevenger type apparatus. Forty constituents were identified via GC and GC-MS analysis. β-caryophyllene (32.5%) and α-humulene (17.8%) were the most abundant components. The evaluation of free radical scavenging activity using stable DPPH free radical showed that the volatile oil exhibits a moderate antioxidant activity and reduces DPPH to 50% at EC₅₀ value of 1230 μg mL^? 1.