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891.
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A simple procedure for the synthesis of 1‐[4‐(2,3‐dihydro‐1, 4‐benzodioxin‐2‐yl) amide‐6, 7‐dimethoxy‐2‐quazolinyl]‐4‐(1,4‐bensodioxan‐2‐yl‐carbonyl) piperazine is described. 相似文献
894.
895.
896.
Natalya Vinogradova Irina Odinets Pavel Petrovskii Konstantin Lyssenko Tatyana Mastryukova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8-9):1957-1958
Reduction of both individual diastereomers of 2-oxo-1,2-thiaphosphacyclanes by HSiCl 3 proceeds with retention of cyclic structure, cyano-group, and stereochemical configuration. 相似文献
897.
898.
899.
Iryna N. Berdichevets Hristina R. Shimshilashvili Iryna M. Gerasymenko Yana R. Sindarovska Yuriy V. Sheludko Irina V. Goldenkova-Pavlova 《Analytical and bioanalytical chemistry》2010,397(6):2289-2293
Thermostable lichenase encoded by licB gene of Clostridium thermocellum can be used as a reporter protein in plant, bacterial, yeast, and mammalian cells. It has important advantages of high sensitivity
and specificity in qualitative and quantitative assays. Deletion variants of LicB (e.g., LicBM3) retain its enzymatic activity
and thermostability and can be expressed in translational fusion with target proteins without compromising with their properties.
Fusion with the lichenase reporter is especially convenient for the heterologous expression of proteins whose analysis is
difficult or compromised by host enzyme activities, as it is in case of fatty acid desaturases occurring in all groups of
organisms. Recombinant desaturase-lichenase genes can be used for creating genetically modified (GM) plants with improved
chill tolerance. Development of an analytical method for detection of fused desaturase-lichenase transgenes is necessary both
for production of GM plants and for their certification. Here, we report a multiplex polymerase chain reaction method for
detection of desA and desC desaturase genes of cyanobacteria Synechocystis sp. PCC6803 and Synechococcus vulcanus, respectively, fused to licBM3 reporter in GM plants. 相似文献
900.
Yulia A. Piskun Irina V. Vasilenko Sergei V. Kostjuk Kirill V. Zaitsev Galina S. Zaitseva Sergei S. Karlov 《Journal of polymer science. Part A, Polymer chemistry》2010,48(5):1230-1240
The titanium complexes with one ( 1a , 1b , 1c ) and two ( 2a , 2b ) dialkanolamine ligands were used as initiators in the ring‐opening polymerization (ROP) of ε‐caprolactone. Titanocanes 1a and 1b initiated living ROP of ε‐caprolactone affording polymers whose number‐average molecular weights (Mn) increased in direct proportion to monomer conversion (Mn ≤ 30,000 g mol?1) in agreement with calculated values, and were inversely proportional to initiator concentration, while the molecular weight distribution stayed narrow throughout the polymerization (Mw/Mn ≤ 1.2 up to 80% monomer conversion). 1H‐NMR and MALDI‐TOF‐MS studies of the obtained poly(ε‐caprolactone)s revealed the presence of an isopropoxy group originated from the initiator at the polymer termini, indicating that the polymerization takes place exclusively at the Ti–OiPr bond of the catalyst. The higher molecular weight polymers (Mn ≤ 70,000 g mol?1) with reasonable MWD (Mw/Mn ≤ 1.6) were synthesized by living ROP of ε‐caprolactone using spirobititanocanes ( 2a , 2b ) and titanocane 1c as initiators. The latter catalysts, according MALDI‐TOF‐MS data, afford poly(ε‐caprolactone)s with almost equal content of α,ω‐dihydroxyl‐ and α‐hydroxyl‐ω(carboxylic acid)‐terminated chains arising due to monomer insertion into “Ti–O” bond of dialkanolamine ligand and from initiation via traces of water, respectively. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1230–1240, 2010 相似文献