52972-61-9Relevant articles and documents
Bond-specific dissociation following excitation energy transfer for distance constraint determination in the gas phase
Hendricks, Nathan G.,Lareau, Nichole M.,Stow, Sarah M.,McLean, John A.,Julian, Ryan R.
, p. 13363 - 13370 (2014)
Herein, we report chemistry that enables excitation energy transfer (EET) to be accurately measured via action spectroscopy on gaseous ions in an ion trap. It is demonstrated that EET between tryptophan or tyrosine and a disulfide bond leads to excited state, homolytic fragmentation of the disulfide bond. This phenomenon exhibits a tight distance dependence, which is consistent with Dexter exchange transfer. The extent of fragmentation of the disulfide bond can be used to determine the distance between the chromophore and disulfide bond. The chemistry is well suited for the examination of protein structure in the gas phase because native amino acids can serve as the donor/acceptor moieties. Furthermore, both tyrosine and tryptophan exhibit unique action spectra, meaning that the identity of the donating chromophore can be easily determined in addition to the distance between donor/acceptor. Application of the method to the Trpcage miniprotein reveals distance constraints that are consistent with a native-like fold for the +2 charge state in the gas phase. This structure is stabilized by several salt bridges, which have also been observed to be important previously in proteins that retain native-like structures in the gas phase. The ability of this method to measure specific distance constraints, potentially at numerous positions if combined with site-directed mutagenesis, significantly enhances our ability to examine protein structure in the gas phase.
MANNICH REACTIONS OF Π-EXCESSIVE HETEROCYLES USING BIS-(DIALKYLAMINO)METHANES AND ALKOXYDIALKYLAMINOMETHANES ACTIVATED WITH ACETYL CHLORIDE OR SULPHUR DIOXIDE
Eyley, Stephen C.,Heaney, Harry,Papageorgiou, George,Wilkins, Robert F.
, p. 2997 - 3000 (1988)
Π-Excessive heterocyles react rapidly with bis(dialkylamino)methanes (aminals) and alkoxydialkylaminomethanes (aminol ethers) in acetonitrile to afford Mannnich bases in good yields when ativated by means of an acidi reagent suh as acetyl chloride or sulphur dioxide: the principal ompound studied was N-methylpyrrole.
Substitution of the Dimethylamino Group in Gramines and One-Pot Cyclization to Tetrahydro-β-carbolines Using a Triazine-Based Activating Agent
Fujita, Hikaru,Nishikawa, Riho,Sasamoto, Ozora,Kitamura, Masanori,Kunishima, Munetaka
, p. 8380 - 8391 (2019/07/08)
A new method for the substitution of 3-[(dimethylamino)methyl]indoles (gramines) with malonate-based nucleophiles was developed using 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) as the activating agent for the dimethylamino group. The reaction was completed in 1.5-6 h at room temperature in the presence of a tert-amine base and lithium salt. CDMT afforded superior results to methyl iodide, a common activating agent for the dimethylamino group in Mannich bases, particularly in the reactions of 1-substituted gramines. The reactivity of the possible intermediates, bis(indol-3-ylmethyl)dimethylammonium salts, was examined to obtain mechanistic insights on the reaction. This substitution method with CDMT enabled the sequential transformation of gramines: substitution with (N-alkylidene)aminomalonates followed by the Pictet-Spengler reaction under acidic conditions afforded 1,2,3,4-tetrahydro-β-carboline derivatives in one pot.
Visible-Light-Mediated α-Oxygenation of 3-(N,N-Dimethylaminomethyl)-Indoles to Aldehydes
Stanek, Filip,Paw?owski, Robert,Mlynarski, Jacek,Stodulski, Maciej
supporting information, p. 6624 - 6628 (2018/10/20)
The visible-light-mediated oxygenation of 3-N,N-(dimethylaminomethyl)-indoles bearing various substituents afforded a series of 3-carbaindole derivatives. Herein we describe the reaction scope, a plausible mechanism and a practical application of this transformation in the formal synthesis of (–)-vincorine is described as well.
Imidazo[4,5-a]quinindolines as highly effective antibacterial agents
Pordel, Mehdi,Ramezani, Shirin,Jajarmi, Maryam,Sokhanvar, Mina
, p. 106 - 110 (2016/02/18)
Resistance to antimicrobial agents is a concern that exists globally and has a considerable impact on human and animal health, so that the discovery of new antibacterial compounds has become increasingly more important in combating infectious disease. In this paper, imidazo[4,5-a]quinindolines are introduced as new antibacterial agents against Gram-positive and Gram-negative bacteria. These pentacyclic compounds are synthesized by the reaction of N-alkyl-5-nitrobenzimidazoles with 2-(1-alkyl-1H-3-indolyl)acetonitrile under basic conditions in excellent yields. The structures of newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR, and mass spectral data. The antibacterial activities of the synthesized compounds were screened against standard strains of two Gram-positive and two Gram-negative bacteria using the broth microdilution method. Most of the compounds studied showed promising activities against both types of bacteria.
