3.5- Dimethoxy-4-hydroxycinnamic acid

The MALDI-TOF technique was first developed for the analysis of large biomolecules (Karas and others 1987). This technique presents some interesting characteristics. Of these, the high speed of analysis and the sensitivity of the technique have been pointed out as important advantages compared with other methods. In MALDI the samples are cocrystallized with a matrix that is usually composed of organic compounds, such as 3,5-dimethoxy-4-hydroxycinnamic acid (sinapic acid), 2, 4, 6 -trihydroxyacetophenone, a-cyano-4-hydroxycinnamic acid (alpha-cyano or alpha-matrix), and 2,5-dihydroxybenzoic acid (DHB). After the cocrystallization, the laser is fired and the matrix absorbs energy and allows a soft ionization of the samples. Afterward the ions are analyzed by a TOF mass spectrometer. 

Dimethoxy-4-hydroxycinnamic acid see 3-(4-hydroxy-3,5-dimethoxyphenyl)acrylic acid. 

MALDI mass spectra were acquired on a Broker Reflex mass spectrometer equipped with a 337 nm nitrogen laser and a multiple sample stage source. The spectra were acquired in linear mode, represent the sum of 20 laser shots, and are un-smoothed. All ions were desorbed at a laser power just above threshold, at an ion extraction voltage of 30 kV. The matrix used was a saturated solution of 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid, Aldrich Chemicals) in a 1 1 water/acetonitrile solution. Low-mass matrix ions were deflected by the application of a voltage pulse. 

Cl1 HI205 3,5-dimethoxy-4-hydroxycinnamic acid, predom 530-59-6 25.00 1.2459 2 22126 Cl 1HI402 1 -(4-hydroxy-3-methylphenyl)-2-methyl-1 -prop 73206-57-2 22.09 1.0291 2... 

Hydroxycinnamic acids 1057—see also trans-3,5-Dimethoxy-4-hydroxycinnamic acid, tratts-3-Methoxy-4-hydroxycinnamic acid mass spectra of 285... 

Table 11.1 Overview of studies for profiling human pathogens with MALDI-TOF MS at the strain level Examples of strain categorization (A), strain differentiation (B), and strain identification (C). MRSA methicillin-resistant Staphylococcus aureus, MSSA methicillin-sensitive S. aureus, L library-based approach, P proteomics-based approach, CHCA a-cyano-4-hydroxycinnamic acid, CMBT 5-chloro-2-mercaptobenzothiazole, DHB 2-hydroxy-5-methoxy benzoic acid, FA ferulic acid, HABA 2,4-hydroxyphenylazobenzoic acid, SA 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid), THAP 2,4,6-trihydroxyacetophenon. Adapted and modified from Sandrin et al. (2013)... 

Commonly, 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid, SA) [85] and 2,5-dihydroxybenzoic acid (DHB) [17,50] are suitable for MALDI of pro-... 

While the main phenolic compounds of olive oil, hydroxytyrosol and oleuropein, give the oil its bitter and pungent taste, the major phenolic compounds in canola seeds are esterified phenolic acids. The main component of the latter is sinapine, the choline-ester of sinapic acid (3,5-dimethoxy-4-hydroxycinnamic acid) (Krygier et al., 1982). Some free phenolic compounds of about 15% are also present with... 

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