Design and Synthesis of Novel Chiral Dirhodium(II) Carboxylate Complexes for Asymmetric Cyclopropanation Reactions

During the design and synthesis of new chemotherapeutic agents for prostatic carcinoma based on phosphorylated agents which might be enzyme-activated to cytotoxicity, phosphorylcholine, [(CH3)3+NCH2CH2OPO3Ca]Cl-, has been indicated to be a very specific substrate for prostatic acid phosphatase (PAP). This phenomenon has led to the development of specific histochemical and ultracytochemical methods for PAP using modifications of the Gomori lead method for acid phosphatase. Comparative histochemical results in prostate and kidney of the rat have been published earlier with phosphorylcholine (PC) and β-glycerophosphate (βGP). We now report the ultracytochemical results.Minced tissues were fixed in 3% glutaraldehyde-0.1 M phosphate buffered (pH 7.4) for 1.5 hr and rinsed overnight in several changes of 0.05 M phosphate buffer (pH 7.0) containing 7.5% sucrose. Tissues were incubated 30 min to 2 hr in Gomori acid phosphatase medium (2) containing 0.1 M substrate, either PC or βGP.

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Tailoring microstructures of materials through biomimetics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148332 ◽

1993 ◽

Vol 51 ◽

pp. 500-501

Author(s):

Mehmet Sarikaya ◽

Ilhan A. Aksay

Keyword(s):

Chemical Properties ◽

Design And Synthesis ◽

Structure Sensitive ◽

Macro Scale ◽

Methods Of Synthesis ◽

Successive Level ◽

Engineering Materials ◽

Physical And Chemical ◽

And Chemical Properties ◽

Synthesis Of Materials

Biomimetics involves investigation of structure, function, and methods of synthesis of biological composite materials. The goal is to apply this information to the design and synthesis of materials for engineering applications.Properties of engineering materials are structure sensitive through the whole spectrum of dimensions from nanometer to macro scale. The goal in designing and processing of technological materials, therefore, is to control microstructural evolution at each of these dimensions so as to achieve predictable physical and chemical properties. Control at each successive level of dimension, however, is a major challenge as is the retention of integrity between successive levels. Engineering materials are rarely fabricated to achieve more than a few of the desired properties and the synthesis techniques usually involve high temperature or low pressure conditions that are energy inefficient and environmentally damaging.In contrast to human-made materials, organisms synthesize composites whose intricate structures are more controlled at each scale and hierarchical order.

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Design and synthesis of azaisoflavones

Planta Medica ◽

10.1055/s-0028-1084783 ◽

2008 ◽

Vol 74 (09) ◽

Author(s):

B Kang ◽

YJ Jung ◽

R Jeon

Keyword(s):

Design And Synthesis

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Computer Modeling-Assisted Design And Synthesis Of Flavonols Derivatives As Proteasome Inhibitors

Planta Medica ◽

10.1055/s-0036-1578757 ◽

2016 ◽

Vol 82 (05) ◽

Author(s):

KY Orabi ◽

MS Abaza ◽

KA ElSayed ◽

AY Elnagar ◽

SI Faggal ◽

...

Keyword(s):

Computer Modeling ◽

Proteasome Inhibitors ◽

Design And Synthesis

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Design and synthesis of novel Azatidinones analogues as potential antimicrobials

Journal of Chemical Biological and Physical Sciences ◽

10.24214/jcbps.a.7.3.68187 ◽

2017 ◽

Vol 7 (3) ◽

Cited By ~ 1

Keyword(s):

Design And Synthesis

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Design and Synthesis of Amide Derivatives of Melampomagnolamine: Acted as Potent Anti-cancer Agents

10.26226/morressier.57d6b2bbd462b8028d88edfe ◽

2016 ◽

Author(s):

Venumadhav Janganati

Keyword(s):

Design And Synthesis ◽

Amide Derivatives ◽

Anti Cancer ◽

Derivatives Of

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General Cyclopropane Assembly via Enantioselective Redox-Active Carbene Transfer to Aliphatic Olefins

10.26434/chemrxiv.7436795 ◽

2018 ◽

Author(s):

Marc Montesinos-Magraner ◽

Matteo Costantini ◽

Rodrigo Ramirez-Contreras ◽

Michael E. Muratore ◽

Magnus J. Johansson ◽

...

Keyword(s):

Total Synthesis ◽

Asymmetric Synthesis ◽

Chemical Space ◽

Synthetic Approach ◽

Asymmetric Cyclopropanation ◽

Redox Active ◽

Wide Range ◽

Leaving Group ◽

Stereoelectronic Properties ◽

Carbene Transfer

Asymmetric cyclopropane synthesis currently requires bespoke strategies, methods, substrates and reagents, even when targeting similar compounds. This limits the speed and chemical space available for discovery campaigns. Here we introduce a practical and versatile diazocompound, and we demonstrate its performance in the first unified asymmetric synthesis of functionalized cyclopropanes. We found that the redox-active leaving group in this reagent enhances the reactivity and selectivity of geminal carbene transfer. This effect enabled the asymmetric cyclopropanation of a wide range of olefins including unactivated aliphatic alkenes, enabling the 3-step total synthesis of (–)-dictyopterene A. This unified synthetic approach delivers high enantioselectivities that are independent of the stereoelectronic properties of the functional groups transferred. Our results demonstrate that orthogonally-differentiated diazocompounds are viable and advantageous equivalents of single-carbon chirons.

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Design and Synthesis of Two-Dimensional Covalent Organic Frameworks with Four-Arm Cores: Prediction of Remarkable Ambipolar Charge-Transport Properties

10.26434/chemrxiv.7766786.v2 ◽

2019 ◽

Author(s):

Simil Thomas ◽

Hong Li ◽

Raghunath R. Dasari ◽

Austin Evans ◽

William Dichtel ◽

...

Keyword(s):

Charge Transport ◽

Organic Semiconductors ◽

Density Functional ◽

Polymer Networks ◽

Two Dimensional ◽

Covalent Organic Frameworks ◽

X Ray Diffraction ◽

Zinc Porphyrin ◽

Design And Synthesis ◽

Predicted Values

We have considered three two-dimensional (2D) π-conjugated polymer networks (i.e., covalent organic frameworks, COFs) materials based on pyrene, porphyrin, and zinc-porphyrin cores connected via diacetylenic linkers. Their electronic structures, investigated at the density functional theory global-hybrid level, are indicative of valence and conduction bands that have large widths, ranging between 1 and 2 eV. Using a molecular approach to derive the electronic couplings between adjacent core units and the electron-vibration couplings, the three π-conjugated 2D COFs are predicted to have ambipolar charge-transport characteristics with electron and hole mobilities in the range of 65-95 cm2V-1s-1. Such predicted values rank these 2D COFs among the highest-mobility organic semiconductors. In addition, we have synthesized the zinc-porphyrin based 2D COF and carried out structural characterization via powder X-ray diffraction and surface area analysis, which demonstrates the feasability of these electroactive networks.

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