Chelate-Controlled Synthesis of Racemic <i>a</i><i>nsa</i>-Zirconocenes
作者:Matthew D. LoCoco、Xingwang Zhang、Richard F. Jordan
DOI:10.1021/ja046629+
日期:2004.11.1
The reaction of ZrPhN(CH2)(3)NPh}Cl-2(THF)(2) (5) with lithium ansa-bis-indenyl reagents Li-2[XBI]-(Et2O) (XBI = (1-indenyl)(2)SiMe2 (SBI, 7a), (2-methyl-1-indenyl)(2)SiMe2 (MSBI, 7b), (2-methyl-4,5-benz-1-indenyl)(2)SiMe2 (MBSBI, 7c), (2-methyl-4-phenyl-1-indenyl)(2)SiMe2 (MPSBI, 7d), and 1,2-(1-indenyl)(2)ethane (EBI, 7e)) affords rac-(XBI)ZrPhN(CH2)(3)NPh} (8a-e) in high yield. The meso isomers were not detected by H-1 NMR. X-ray crystallographic studies show that the ZrPhN(CH2)(3)NPh) rings in 5, 8a, 8c, and (C5H5)(2)-ZrPhN(CH2)(3)NPh} (10) adopt twist conformations that position the N-Ph groups on opposite sides of the N-Zr-N plane. This conformation complements the metallocene structures of rac-8a-e but would destabilize the corresponding meso isomers. It is proposed that the ZrPhN(CH2)(3)NPh} ring adopts a similar twist conformation in the stereodetermining transition state for addition of the second indenyl ring in these reactions, which leads to a preference for rac products. The results of metallocene syntheses from other Zr amide precursors support this proposal. 8a-e are converted to the corresponding rac-(XBI)ZrCl2 complexes (9a-e) by reaction with HCl.
A CYANINE-BASED PROBE\TAG-PEPTIDE PAIR FOR FLUORESCENCE PROTEIN IMAGING AND FLUORESCENCE PROTEIN IMAGING METHODS
申请人:BATTELLE MEMORIAL INSTITUTE
公开号:EP2152810A1
公开(公告)日:2010-02-17
[EN] A CYANINE-BASED PROBE\TAG-PEPTIDE PAIR FOR FLUORESCENCE PROTEIN IMAGING AND FLUORESCENCE PROTEIN IMAGING METHODS<br/>[FR] SONDE À BASE DE CYANINE IMAGERIE DE PROTÉINE DE FLUORESCENCE ET PROCÉDÉS D'IMAGERIE DE PROTÉINE DE FLUORESCENCE
申请人:BATTELLE MEMORIAL INSTITUTE
公开号:WO2008127768A1
公开(公告)日:2008-10-23
[EN] A molecular probe comprises two arsenic atoms and at least one cyanine based moiety. A method of producing a molecular probe includes providing a molecule having a first formula, treating the molecule with HgOAc, and subsequently transmetallizing with AsCI3. The As is liganded to ethanedithiol to produce a probe having a second formula. A method of labeling a peptide includes providing a peptide comprising a tag sequence and contacting the peptide with a biarsenical molecular probe. A complex is formed comprising the tag sequence and the molecular probe. A method of studying a peptide includes providing a mixture containing a peptide comprising a peptide tag sequence, adding a biarsenical probe to the mixture, and monitoring the fluorescence of the mixture. [FR] L'invention concerne une sonde moléculaire qui comprend deux atomes d'arsenic et au moins une fraction basée sur la cyanine. Un procédé de production de sonde moléculaire consiste à produire une molécule possédant une première formule, à traiter la molécule avec du HgOAc, puis à la transmétalliser avec de l'AsCI3. L'As est lié à de l'éthanedithiol afin de produire une sonde possédant une seconde formule. Un procédé d'étiquetage d'un peptide consiste à fournir une séquence d'étiquette et à mettre en contact le peptide avec une sonde moléculaire biarsénicale. Un complexe comprenant la séquence d'étiquette et la sonde moléculaire est formé. L'invention concerne également un procédé d'anaylse d'un peptide qui consiste à produire un mélange contenant un peptide à séquence d'étiquette peptidique, à ajouter une sonde biarsénicale au mélange, et à surveiller la fluorescence du mélange.
An Efficient Synthesis of N,N'-Substituted Symmetrical Diamines
Abstract N,N'-substituted symmetrical diamines are readily prepared in high yields in a one-pot procedure from diazidoalcanes and dichloroboranes. This approach has been extended to the synthesis of thermine, a tetramine isolated from Thermus Thermophilus.