Poly(2‐oxazoline)s terminated with 2,2′‐imino diacetic acid form noncovalent polymer–enzyme conjugates that are highly active in organic solvents

2018 ◽  
Vol 116 (2) ◽  
pp. 272-282 ◽  
Author(s):  
Montasser Hijazi ◽  
Pia Spiekermann ◽  
Christian Krumm ◽  
Joerg C. Tiller
Keyword(s):  
Organic Solvents ◽  
Acid Form ◽  
Diacetic Acid ◽  
Highly Active ◽  
Imino Diacetic Acid

scholarly journals Dinuclear thiazolylidene copper complex as highly active catalyst for azid–alkyne cycloadditions

2016 ◽  
Vol 12 ◽  
pp. 1566-1572 ◽  
Author(s):  
Anne L Schöffler ◽  
Ata Makarem ◽  
Frank Rominger ◽  
Bernd F Straub
Keyword(s):  
Acetic Acid ◽  
Organic Solvents ◽  
Copper Complex ◽  
Room Temperature ◽  
Active Catalyst ◽  
Catalyst Design ◽  
Ancillary Ligand ◽  
Click Reactions ◽  
Highly Active ◽  
Cost Efficient

A dinuclear N-heterocyclic carbene (NHC) copper complex efficiently catalyzes azide–alkyne cycloaddition (CuAAC) “click” reactions. The ancillary ligand comprises two 4,5-dimethyl-1,3-thiazol-2-ylidene units and an ethylene linker. The three-step preparation of the complex from commercially available starting compounds is more straightforward and cost-efficient than that of the previously described 1,2,4-triazol-5-ylidene derivatives. Kinetic experiments revealed its high catalytic CuAAC activity in organic solvents at room temperature. The activity increases upon addition of acetic acid, particularly for more acidic alkyne substrates. The modular catalyst design renders possible the exchange of N-heterocyclic carbene, linker, sacrificial ligand, and counter ion.

scholarly journals Rational Design for Enhanced Acyltransferase Activity in Water Catalyzed by the Pyrobaculum calidifontis VA1 Esterase

2021 ◽  
Vol 9 (8) ◽  
pp. 1790
Author(s):  
Amanda Staudt ◽  
Henrik Terholsen ◽  
Jasmin Kaur ◽  
Henrik Müller ◽  
Simon P. Godehard ◽  
...  
Keyword(s):  
Organic Solvents ◽  
Rational Design ◽  
Bulk Water ◽  
Acyl Transfer ◽  
Acyl Donor ◽  
Acyltransferase Activity ◽  
Pyrobaculum Calidifontis ◽  
Synthetic Strategy ◽  
Highly Active ◽  
Acyl Transfer Activity

Biocatalytic transesterification is commonly carried out employing lipases in anhydrous organic solvents since hydrolases usually prefer hydrolysis over acyl transfer in bulk water. However, some promiscuous acyltransferases can catalyze acylation in an aqueous solution. In this study, a rational design was performed to enhance the acyltransferase selectivity and substrate scope of the Pyrobaculum calidifontis VA1 esterase (PestE). PestE wild type and variants were applied for the acylation of monoterpene alcohols. The mutant PestE_I208A is selective for (–)-menthyl acetate (E-Value = 55). Highly active acyltransferases were designed, allowing for complete conversion of (–)-citronellol to citronellyl acetate. Additionally, carvacrol was acetylated but with lower conversions. To the best of our knowledge, this is the first example of the biocatalytic acylation of a phenolic alcohol in bulk water. In addition, a high citronellol conversion of 92% was achieved with the more environmentally friendly and inexpensive acyl donor ethyl acetate using PestE_N288F as a catalyst. PestE_N288F exhibits good acyl transfer activity in an aqueous medium and low hydrolysis activity at the same time. Thus, our study demonstrates an alternative synthetic strategy for acylation of compounds without organic solvents.

Preparation and characterization of imino diacetic acid functionalized alginate beads for removal of contaminants from waste water: I. methylene blue cationic dye model

2012 ◽  
Vol 40 (1-3) ◽  
pp. 15-23 ◽  
Author(s):  
Mohamed Samir Mohy Eldin ◽  
Emad Ali Soliman ◽  
Ahmed Abdel Fattah Elzatahry ◽  
Mohamed Ramadan Elaassar ◽  
Marwa Farouk Elkady ◽  
...  
Keyword(s):  
Waste Water ◽  
Methylene Blue ◽  
Alginate Beads ◽  
Cationic Dye ◽  
Diacetic Acid ◽  
Removal Of Contaminants ◽  
Imino Diacetic Acid ◽  
Methylene Blue Cationic Dye

High chemiluminescence activity of an FeIII–TAML activator in aqueous–organic media and its use in the determination of organic peroxides

The Analyst ◽  
2015 ◽  
Vol 140 (9) ◽  
pp. 2964-2968 ◽  
Author(s):  
Alexandra S. Demiyanova ◽  
Ivan Yu. Sakharov
Keyword(s):  
Benzoyl Peroxide ◽  
Organic Solvents ◽  
Organic Media ◽  
Organic Peroxides ◽  
Peroxidase Mimic ◽  
Butyl Hydroperoxide ◽  
Highly Active

Using FeIII–TAML, highly active peroxidase mimic, the sensitive chemiluminescence assays for the determination of benzoyl peroxide and tert-butyl hydroperoxide in the presence of organic solvents were developed.

Is hepato-imino diacetic acid scan a better imaging modality than abdominal ultrasound for diagnosing acute cholecystitis?

2015 ◽  
Vol 210 (3) ◽  
pp. 473-482 ◽  
Author(s):  
Christodoulos Kaoutzanis ◽  
Eric Davies ◽  
Stefan W. Leichtle ◽  
Kathleen B. Welch ◽  
Suzanne Winter ◽  
...  
Keyword(s):  
Acute Cholecystitis ◽  
Imaging Modality ◽  
Abdominal Ultrasound ◽  
Diacetic Acid ◽  
Imino Diacetic Acid
Sign in / Sign up

Export Citation Format

Share Document