INTERACTIVE IIR SC MULTIRATE COMPILER APPLIED TO MULTISTAGE DECIMATOR DESIGN

2007 ◽  
Vol 16 (04) ◽  
pp. 517-525 ◽  
Author(s):  
PHILLIP N. CHEONG ◽  
R. P. MARTINS
Keyword(s):  
Building Block ◽  
Building Blocks ◽  
Automated Design ◽  
Operational Amplifiers ◽  
Efficient Synthesis ◽  
Design And Synthesis ◽  
Interactive Architecture ◽  
Specific Stage

This paper proposes an interactive architecture compiler for SC multirate circuits that allows the automated design from the frequency specifications to the building block implementation, applied to the design and synthesis of multistage SC decimators. The compiler provides a library of different topologies that comprises a few independent multi-decimation building blocks. New building blocks defined by the users are also available for the design of a specific stage. A design example of a 7th order SC decimator illustrates the efficient synthesis of the corresponding resulting circuits that achieve the required anti-aliasing amplitude responses with respect to the speed requirements of the operational amplifiers and also the minimum capacitance spread and total capacitor area.

scholarly journals Phosphonate reagents and building blocks in the synthesis of bioactive compounds, natural products and medicines

2019 ◽  
Vol 91 (5) ◽  
pp. 811-838 ◽  
Author(s):  
Marian Mikołajczyk
Keyword(s):  
Building Block ◽  
Methyl Esters ◽  
Building Blocks ◽  
Biologically Active ◽  
Type I ◽  
Antiulcer Drug ◽  
Total Syntheses ◽  
Prostaglandin Analogues ◽  
Design And Synthesis ◽  
Neplanocin A

Abstract This account outlines the results obtained in the author’s laboratory on the application of phosphonates in the synthesis of various classes of biologically active cyclopentenones and cyclopentanones. In the first place two general methods for the synthesis of mono-, 1,2- and 1,4-dicarbonyl compounds are presented. The first is based on the use of α-phosphoryl sulfides in conjunction with the Horner reaction while in the second method the oxygenation reaction of α-phosphonate carbanion is a key step. The utility of these two approaches to 1,4-diketones as precursors of cyclopentenones was exemplified by the synthesis of dihydrojasmone and (Z)-jasmone. The use of simple phosphonates, α-phosphoryl sulfides and β- and γ-ketophosphonates as starting reagents in the synthesis of cyclopentanoid antibiotics (methylenomycin B, racemic desepoxy-4,5-didehydromethylenomycin, enantiomeric sarkomycins) is presented. The synthesis and reactivity of achiral 3-(phosphorylmethyl)cyclopent-2-enone and chiral diastereoisomeric camphor protected 3-(phosphorylmethyl)-4,5-dihydroxycyclopent-2-enones as building blocks is discussed as a platform for developing a new access to a variety of bioactive cyclopentenones. The utility and value of achiral phosphonate building block is demonstrated by the synthesis of racemic and enantiopure prostaglandin B1 methyl esters and enantiomeric phytoprostanes B1 type I and II. The range of biologically active compounds prepared from chiral diastereoisomeric cyclopentenone phosphonates is wider. Herein the total syntheses of the following target compounds are presented: enantiomeric isoterreins, natural (−)-neplanocin A and its unnatural (+)-enantiomer, anticancer prostaglandin analogues (enantiomers of TEI-9826, NEPP-11, iso-NEPP-11). The design and synthesis of racemic and four enantiopure stereoisomers of an antiulcer drug rosaprostol is also described.

scholarly journals Generation of Bis(ferrocenyl)silylenes from Siliranes

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5917
Author(s):  
Yang Pan ◽  
Shogo Morisako ◽  
Shinobu Aoyagi ◽  
Takahiro Sasamori
Keyword(s):  
Transition Metal ◽  
Building Block ◽  
Building Blocks ◽  
Redox Behavior ◽  
Organosilicon Compounds ◽  
Design And Synthesis ◽  
Mild Conditions ◽  
Redox Active ◽  
Electronic Perturbation ◽  
Active Transition

Divalent silicon species, the so-called silylenes, represent attractive organosilicon building blocks. Isolable stable silylenes remain scarce, and in most hitherto reported examples, the silicon center is stabilized by electron-donating substituents (e.g., heteroatoms such as nitrogen), which results in electronic perturbation. In order to avoid such electronic perturbation, we have been interested in the chemistry of reactive silylenes with carbon-based substituents such as ferrocenyl groups. Due to the presence of a divalent silicon center and the redox-active transition metal iron, ferrocenylsilylenes can be expected to exhibit interesting redox behavior. Herein, we report the design and synthesis of a bis(ferrocenyl)silirane as a precursor for a bis(ferrocenyl)silylene, which could potentially be used as a building block for redox-active organosilicon compounds. It was found that the isolated bis(ferrocenyl)siliranes could be a bottleable precursor for the bis(ferrocenyl)silylene under mild conditions.

scholarly journals Design and Synthesis of Crown Ether Functionalized Imidazoles as a New type of Building Blocks

2012 ◽  
Vol 9 (4) ◽  
pp. 2128-2133
Author(s):  
Sheng-Hui Li ◽  
Jing Xia
Keyword(s):  
Crown Ether ◽  
Elemental Analysis ◽  
Building Blocks ◽  
Efficient Synthesis ◽  
Esi Ms ◽  
Design And Synthesis ◽  
H Nmr ◽  
New Type

A simple, convenient and efficient synthesis for a series of crown ether functionalized imidazoles from benzo-15-crown-5 (B15C5), benzo-18-crown-6 (B18C6), imidazole (Im), 2-methylimidazole (mIm), benzimidazole (bIm) and 2-methyl benzimidazole (mbIm) is reported. All these compounds obtained were characterized by IR,1H NMR, ESI-MS and elemental analysis.

Thienopyrrolocarbazoles: New Building Blocks for Functional Organic Materials

2019 ◽  
Author(s):  
Dorian Bader ◽  
Johannes Fröhlich ◽  
Paul Kautny
Keyword(s):  
Building Block ◽  
Organic Materials ◽  
Building Blocks ◽  
Molecular Properties ◽  
The Family ◽  
Facile Preparation

The facile preparation of three regioisomeric thienopyrrolocarbazoles applying a convenient C-H activation approach is presented. Derived from indolo[3,2,1-<i>jk</i>]carbazole, the incorporation of thiophene into the triarylamine framework significantly impacted the molecular properties of the parent scaffold. The developed thienopyrrolocarbazoles enrich the family of triarylamine donors and constitute a novel building block for functional organic materials.

Thienopyrrolocarbazoles: New Building Blocks for Functional Organic Materials

2019 ◽  
Author(s):  
Dorian Bader ◽  
Johannes Fröhlich ◽  
Paul Kautny
Keyword(s):  
Building Block ◽  
Organic Materials ◽  
Building Blocks ◽  
Molecular Properties ◽  
The Family ◽  
Facile Preparation

The facile preparation of three regioisomeric thienopyrrolocarbazoles applying a convenient C-H activation approach is presented. Derived from indolo[3,2,1-<i>jk</i>]carbazole, the incorporation of thiophene into the triarylamine framework significantly impacted the molecular properties of the parent scaffold. The developed thienopyrrolocarbazoles enrich the family of triarylamine donors and constitute a novel building block for functional organic materials.

Improvement of Gain Accuracy and CMRR of Low Power Instrumentation Amplifier Using High Gain Operational Amplifiers

2020 ◽  
Vol 12 (3) ◽  
pp. 168-174
Author(s):  
Rashmi Sahu ◽  
Maitraiyee Konar ◽  
Sudip Kundu
Keyword(s):  
Low Power ◽  
Building Blocks ◽  
High Gain ◽  
The Other ◽  
Operational Amplifiers ◽  
Instrumentation Amplifier ◽  
Biomedical Signals ◽  
Op Amp ◽  
Op Amps ◽  
Multi Stage

Background: Sensing of biomedical signals is crucial for monitoring of various health conditions. These signals have a very low amplitude (in μV) and a small frequency range (<500 Hz). In the presence of various common-mode interferences, biomedical signals are difficult to detect. Instrumentation amplifiers (INAs) are usually preferred to detect these signals due to their high commonmode rejection ratio (CMRR). Gain accuracy and CMRR are two important parameters associated with any INA. This article, therefore, focuses on the improvement of the gain accuracy and CMRR of a low power INA topology. Objective: The objective of this article is to achieve high gain accuracy and CMRR of low power INA by having high gain operational amplifiers (Op-Amps), which are the building blocks of the INAs. Methods: For the implementation of the Op-Amps and the INAs, the Cadence Virtuoso tool was used. All the designs and implementation were realized in 0.18 μm CMOS technology. Results: Three different Op-Amp topologies namely single-stage differential Op-Amp, folded cascode Op-Amp, and multi-stage Op-Amp were implemented. Using these Op-Amp topologies separately, three Op-Amp-based INAs were realized and compared. The INA designed using the high gain multistage Op-Amp topology of low-frequency gain of 123.89 dB achieves a CMRR of 164.1 dB, with the INA’s gain accuracy as good as 99%, which is the best when compared to the other two INAs realized using the other two Op-Amp topologies implemented. Conclusion: Using very high gain Op-Amps as the building blocks of the INA improves the gain accuracy of the INA and enhances the CMRR of the INA. The three Op-Amp-based INA designed with the multi-stage Op-Amps shows state-of-the-art characteristics as its gain accuracy is 99% and CMRR is as high as 164.1 dB. The power consumed by this INA is 29.25 μW by operating on a power supply of ±0.9V. This makes this INA highly suitable for low power measurement applications.

scholarly journals PyroMEMS as Future Technological Building Blocks for Advanced Microenergetic Systems

Micromachines ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 118
Author(s):  
Jean-Laurent Pouchairet ◽  
Carole Rossi
Keyword(s):  
Building Block ◽  
Building Blocks ◽  
Small Scale ◽  
Technological Evolution ◽  
Research Groups ◽  
Function Block ◽  
The Past ◽  
New Methods ◽  
Safety And Reliability ◽  
Electronically Controllable

For the past two decades, many research groups have investigated new methods for reducing the size and cost of safe and arm-fire systems, while also improving their safety and reliability, through batch processing. Simultaneously, micro- and nanotechnology advancements regarding nanothermite materials have enabled the production of a key technological building block: pyrotechnical microsystems (pyroMEMS). This building block simply consists of microscale electric initiators with a thin thermite layer as the ignition charge. This microscale to millimeter-scale addressable pyroMEMS enables the integration of intelligence into centimeter-scale pyrotechnical systems. To illustrate this technological evolution, we hereby present the development of a smart infrared (IR) electronically controllable flare consisting of three distinct components: (1) a controllable pyrotechnical ejection block comprising three independently addressable small-scale propellers, all integrated into a one-piece molded and interconnected device, (2) a terminal function block comprising a structured IR pyrotechnical loaf coupled with a microinitiation stage integrating low-energy addressable pyroMEMS, and (3) a connected, autonomous, STANAG 4187 compliant, electronic sensor arming and firing block.

scholarly journals Lipase Catalyzed Synthesis of Enantiopure Precursors and Derivatives for β-Blockers Practolol, Pindolol and Carteolol

Catalysts ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 503
Author(s):  
Morten Gundersen ◽  
Guro Austli ◽  
Sigrid Løvland ◽  
Mari Hansen ◽  
Mari Rødseth ◽  
...  
Keyword(s):  
Building Block ◽  
Kinetic Resolution ◽  
Enantiomeric Excess ◽  
Catalytic Amount ◽  
Building Blocks ◽  
Β Blocker ◽  
Β Blockers ◽  
Optical Rotations ◽  
Reported Data ◽  
By Products

Sustainable methods for producing enantiopure drugs have been developed. Chlorohydrins as building blocks for several β-blockers have been synthesized in high enantiomeric purity by chemo-enzymatic methods. The yield of the chlorohydrins increased by the use of catalytic amount of base. The reason for this was found to be the reduced formation of the dimeric by-products compared to the use of higher concentration of the base. An overall reduction of reagents and reaction time was also obtained compared to our previously reported data of similar compounds. The enantiomers of the chlorohydrin building blocks were obtained by kinetic resolution of the racemate in transesterification reactions catalyzed by Candida antarctica Lipase B (CALB). Optical rotations confirmed the absolute configuration of the enantiopure drugs. The β-blocker (S)-practolol ((S)-N-(4-(2-hydroxy-3-(isopropylamino)propoxy)phenyl)acetamide) was synthesized with 96% enantiomeric excess (ee) from the chlorohydrin (R)-N-(4-(3-chloro-2 hydroxypropoxy)phenyl)acetamide, which was produced in 97% ee and with 27% yield. Racemic building block 1-((1H-indol-4-yl)oxy)-3-chloropropan-2-ol for the β-blocker pindolol was produced in 53% yield and (R)-1-((1H-indol-4-yl)oxy)-3-chloropropan-2-ol was produced in 92% ee. The chlorohydrin 7-(3-chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one, a building block for a derivative of carteolol was produced in 77% yield. (R)-7-(3-Chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one was obtained in 96% ee. The S-enantiomer of this carteolol derivative was produced in 97% ee in 87% yield. Racemic building block 5-(3-chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one, building block for the drug carteolol, was also produced in 53% yield, with 96% ee of the R-chlorohydrin (R)-5-(3-chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one. (S)-Carteolol was produced in 96% ee with low yield, which easily can be improved.

scholarly journals Dimerization and oligomerization of DNA-assembled building blocks for controlled multi-motion in high-order architectures

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Ling Xin ◽  
Xiaoyang Duan ◽  
Na Liu
Keyword(s):  
Building Block ◽  
Degrees Of Freedom ◽  
Building Blocks ◽  
Single Type ◽  
Hierarchical Assembly ◽  
Optical Responses ◽  
Self Association ◽  
Living Organisms ◽  
Order Structures ◽  
Chiral System

AbstractIn living organisms, proteins are organized prevalently through a self-association mechanism to form dimers and oligomers, which often confer new functions at the intermolecular interfaces. Despite the progress on DNA-assembled artificial systems, endeavors have been largely paid to achieve monomeric nanostructures that mimic motor proteins for a single type of motion. Here, we demonstrate a DNA-assembled building block with rotary and walking modules, which can introduce new motion through dimerization and oligomerization. The building block is a chiral system, comprising two interacting gold nanorods to perform rotation and walking, respectively. Through dimerization, two building blocks can form a dimer to yield coordinated sliding. Further oligomerization leads to higher-order structures, containing alternating rotation and sliding dimer interfaces to impose structural twisting. Our hierarchical assembly scheme offers a design blueprint to construct DNA-assembled advanced architectures with high degrees of freedom to tailor the optical responses and regulate multi-motion on the nanoscale.

Recent progress in the design and synthesis of zeolite-like metal–organic frameworks (ZMOFs)

2021 ◽  
Author(s):  
Xinyao Liu ◽  
Yunling Liu
Keyword(s):  
Building Block ◽  
High Stability ◽  
Recent Progress ◽  
Metal Organic Frameworks ◽  
Excellent Performance ◽  
Design And Synthesis ◽  
Molecular Building Block ◽  
Secondary Building Units ◽  
Metal Organic

ZMOFs are a subset of MOFs that exhibit zeolite-like topologies. Using molecular building block strategy, many ZMOFs with high stability and excellent performance can be rationally designed and synthesized using different secondary building units.

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