Switchable Stereocontrolled Divergent Synthesis Induced by aza‐Michael Addition of Deactivated Primary Amines under Acid Catalysis

Switchable tandem intramolecular aza‐Michael/Michael and double aza‐Michael reactions allow the oriented synthesis of highly functionalised cyclic skeletons. Conjugate addition of deactivated anilines triggers chemo‐ and stereo‐divergent ring‐closure reaction pathways with a striking selectivity depending on reaction conditions.     

Muurolane‐type sesquiterpenes from marine sponge Dysidea cinerea

Seven new muurolane‐type sesquiterpenes, (4R,5R)‐muurol‐1(6),10(14)‐diene‐4,5‐diol (1), (4R,5R)‐muurol‐1(6)‐ene‐4,5‐diol (2), (4R,5R,10R)‐10‐methoxymuurol‐1(6)‐ene‐4,5‐diol (3), (4S)‐4‐hydroxy‐1,10‐seco‐muurol‐5‐ene‐1,10‐dione (4), (4R)‐4‐hydroxy‐1,10‐seco‐muurol‐5‐ene‐1,10‐dione (5), (6S,10S)‐6,10‐dihydroxy‐7,8‐seco‐2,8‐cyclo‐muurol‐4(5),7(11)‐diene‐12‐oic acid (6), and (6R,10S)‐6,10‐dihydroxy‐7,8‐seco‐2,8‐cyclo‐muurol‐4(5),7(11)‐diene‐12‐oic acid (7) were isolated from the marine sponge Dysidea cinerea. Their structures were determined by the combination of spectroscopic and chemical methods, including 1D‐NMR, 2D‐NMR, and CD spectra as well as by comparing the NMR data with those reported in the literature. Copyright © 2013 John Wiley & Sons, Ltd.     

Strained-cyclophane-induced beta-turn template: design, synthesis, and spectroscopic characterization

[structure: see text] Three tetrapeptides incorporating a 14-membered (R(i+1), S(i+2)) cycloisodityrosine at the i + 1 and i + 2 positions were designed and synthesized. Conformational analysis by (1)H NMR and CD spectra as well as molecular modeling indicated that they all adopt a beta-turn conformation. While the CD spectrum of compound 2 is characteristic of the typical type-II beta-turn (maximum at approximately 200 nm and a minimum at approximately 220 nm), that of 1a (atropisomer of 2) is opposite in sign to the expected spectrum of the type-II beta-turn.     

Some imines and azo compounds containing furoxan ring synthesized from methylisoeugenol

Some imines and azo compounds containing furoxan and benzene rings have been prepared starting from methylisoeugenol. The structure of reported compounds has been confirmed by elemental analysis, ms, uv, ir, and nmr spectroscopy. It is shown that, on treatment with Na₂S₂O₄, the nitro group on the benzene ring was reduced to an amino group, but the N←O group of furoxan ring was not. The ¹H‐ and ¹³C nmr signals are assigned based on their spin‐spin splitting patterns, in some cases, NOESY and HMBC spectra are used. The NOESY spectra indicate that the reported imines have E‐configuration. Among 8 tested compounds, there are 5 compounds that exhibit anti‐microbial activity toward Gr+ S. aureus at concentration 12.5μg/mL.     

一种基于提升算法的小波滤波器硬件结构设计

基于提升方法提出了一种有效的双正交(9—7)小波滤波器的硬件实现结构。采用流水线调度技术优化结构设计，其前向滤波器和后向滤波器的实现具有对称性，硬件实现方法简单。采用Verilog HDL对系统设计进行了描述，进行了功能仿真，并选用Xilinx公司的xcv50e-csl44—8在集成软件ISE4．1下进行了综合和映射。     

Transitions de Phase en Series Mesogenes:

The polymorphism of the di(4-alkylphenyl) and di(4-alkoxyphenyl) tetrathiafulvalene (TTF) is investigated by optical, crystallographic and calorimetric methods. All the studied derivatives are mesomorphic. The first mesophase is always a smectic G phase; the second one is a nematic N phase for short chains and a smectic C phase for long chains.

The entropies corresponding to the passage high-temperature crystalline phase C₁ → S_G and to the “melting” (C₁ → mesophases → isotropic phase I) increase with the length of the chain and with the presence of the oxygen atom in the radical.     

Surface Modification of Cellulose Microfibrils with Silane Agent for Eco-Friendly Hydrophobic Coatings

Russian Journal of Applied Chemistry - In this study, an optimized method for surface modification of cellulose microfibrils (CMF) with (3-Aminopropyl) trimethoxysilane (APTMS) for eco-friendly...     

Another characterization of convexity for set-valued maps

We give a new necessary and sufficient condition for convexity of a set-valued map F between Banach spaces. It is established for a closed map F having nonconvex values. The main tool in this paper is the coderivative of F which is constructed with the help of an abstract subdifferential notion of Penot . A detailed discussion is devoted to special cases when the contingent, the Fréchet and the Clarke-Rockafellar subdifFerentials Sixe used as this abstract subdifferential.     

A note on super-hedging for investor–producers

We study the situation of an agent who can trade on a financial market and can also transform some assets into others by means of a production system, in order to price and hedge derivatives on produced goods. This framework is motivated by the case of an electricity producer who wants to hedge a position on the electricity spot price and can trade commodities which are inputs for his system. This extends the essential results of Bouchard and Nguyen (Math Finance, 2011) to continuous time markets. We introduce the generic concept of conditional sure profit along the idea of the no sure profit condition of Rásonyi (Optimality and risk-modern trends in mathematical finance: the Kabanov Fetschrift, 2009). The condition allows one to provide a closedness property for the set of super-hedgeable claims in a very general financial setting. Using standard separation arguments, we then deduce a dual characterization of the latter and provide an application to power futures pricing.     

Dynamics of a stochastic Lotka-Volterra model perturbed by white noise

This paper continues the study of Mao et al. investigating two aspects of the equation