Group efficiency

Group Efficiency Filter type Stain test efficiency, % Arrestance, %... 

Group Efficiency Removal efficiency, %, for particle size of... 

Group Efficiency Air-flow capacity, ftV(min-ft of frontal area) Resistance, in water Dust-holding capacity, g/(1000 fP-min of air-flow capacity)... 

With the exocyclic alkylidene at C-13 properly in place, the elaboration of the l,5-diyn-3-ene moiety can now be addressed. Cleavage of both acetate and trimethylsilyl functions in 86 with basic methanol, followed by triethylsilylation of the newly formed tertiary hydroxyl group, efficiently affords alkyne 25 (86 % overall yield). This substance was regarded as a viable candidate for a Pd-catalyzed coupling reaction.12 Indeed, treatment of 25 with (Z)-chloroenyne 26 in the presence of a catalytic amount of Pd(PPh3)4 and Cu1 results in the formation of enediyne 24 in 91 % yield. 

It has been found that the tris(tert-butyloxycarbonyl) protected hydantoin of 4-piperidone 2, selectively hydrolyses in alkali to yield the N-tert-butyloxycarbonylated piperidine amino acid 3. The hydrolysis, which is performed in a biphasic mixture of THF and 2.0M KOH at room temperature, cleanly partitions the deprotonated 4-amino-N -(tert-butyloxycarbonyl)piperidine-4-carboxylic acid into the aqueous phase of the reaction with minimal contamination of the hydrolysis product, di-tert-butyl iminodicarboxylate, which partitions into the THF layer. Upon neutralization of the aqueous phase with aqueous hydrochloric acid, the zwitterion of the amino acid is isolated. The Bolin procedure to introduce the 9-fluorenylmethyloxycarbonyl protecting group efficiently produces 4.8 This synthesis is a significant improvement over the previously described method9 where the final protection step was complicated by contamination of the hydrolysis side-product, di-tert-butyl iminodicarboxylate, which is very difficult to separate from 4, even by chromatographic means. 

The group efficiencies can be compared with the known binding modes of compounds to infer which parts of the active site are responsible for contributing... 

Electrochemical oxidation is clean, and is, in the presence of activating groups, efficient. The lack of stability of commonly used anodes (except Ebonex, Sect. 2.3) often limits its use. Hydrogen peroxide is an ad hoc expensive oxidant... 

QA requires the efficient analysis of many samples to support routine production release and stability programs. Methods are typically established in the analytical development group. Efficiency and convenience issues, including the speed of media preparation and the relative convenience of data handling and documentation, are important here. While compliance is important in all aspects of the pharmaceutical industry, QA functions must approach compliance perfection. Depending upon the facility, the automated apparatus may be tailored to specific methods with fixed configurations. Dissolution methods may be routine enough that a custom system, optimized for productivity, may be justified. Compliance of USP and use of industry standard apparatus is important to maintain compatibility with other company laboratories or in the case contract laboratory services are required. 

The reaction of hydroxyl group on inorganic particles with reactive polymers having isocyanate (27.28), alkoxysilane (29,30), and chlorosilane (29) groups efficiently gave the polymer-grafted particles [Reactions (9) and (10)]. 

The reaction of secondary amines with 1- 1leaving group efficiency) of the chloroe-thoxide anion as shown in scheme 142 (Ref. 197). 

Ishiyama, T., Takagi, J., Kamon, A., Miyaura, N. Palladium-catalyzed cross-coupling reaction of bis(pinacolato)diboron with vinyl trifiates -substituted by a carbonyl group efficient synthesis of -boryl- -unsaturated carbonyl compounds and their synthetic utility. J. Organomet. Chem. 2003, 687, 284-290. 

Mixed cuprate reagents derived from RLi and (trimethylsilyl)methylcopper(l) are thermally stable yet highly reactive. They transfer the R groups efficiently while giving tetramethylsilane as by-product on workup. ... 

Varying amounts of acridone are produced along with carbazoles when salicyl 2-azidobenzoates (36) are pyrolysed at 400°C. The acridone predominates with the phenyl ester (M.G. Clancy, M.M. Hesabi and 0. Meth-Cohn, Cbm. Comm., 1980, 1112) and later work indicates that the amount of acridone increases as the leaving group efficiency of OR increases (.idem, J. chem. Soc. Perkin I, 1984, 429). Spray pyrolysis of 2,6-disubstituted phenyl 2-azidobenzoates leads to a mixture of 4-substituted 9,10-dihydroacridine and the corresponding acridine, possibly involving ipso attack by the nitrene. 

Verdonk ML, Rees DC (2008) Group efficiency a guideline for hits-to-leads chemistry. ChemMedChem 3 1179-1180... 

Group Efficiency Filter typa 0.3 pm 1.0 pm 5.0 pm 10.G pm areu) Filler Filter... 

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