The Structure of Paraldol

Quantitative analysis of the compounds in synthesis mixtures of 2,2-dimethyl-3-hydroxypropionaldehyde by RP-HPLC and GC

“…In addition, various parameters affect the equilibrium reaction between the monomeric and the dimeric form of DHPAL, which must be taken into account in the analysis. This kind of behaviour is similar to that of other hydroxy aldehydes [4][5][6]. In solution, the equilibrium position depends on the solvent and the temperature [3].…”

Lactols in Hydrolysates of DNA Treated with α-Acetoxy-N-nitrosopyrrolidine or Crotonaldehyde

“…Adducts formed by this pathway are called type 2 adducts. Intermediates 2, 3, and 7 react with H 2 O to produce three solvolysis products: 4-HOBA, which exists mainly as the lactol 2-hydroxyTHF; 3-HOBA, which exists mainly as the dimer paraldol; and crotonaldehyde (2,13,28). Crotonaldehyde reacts with DNA to produce adducts 9-12 as well as the paraldol-releasing adducts (20,21,37).…”

Disentangling Complex Mixtures of Compounds with Near‐Identical 1H and 13C NMR Spectra using Pure Shift NMR Spectroscopy

“…The power of the proposed method is illustrated with the analysis of a challenging real sample from our lab, consisting of a mixture of several unknown compounds that were finally determined as three pairs of diastereoisomeric derivatives. These compounds were the result of a nonselective homoaldol addition of acetaldehyde, followed by the ketalization of the aldehyde group of the homoaldol adduct by its hydrate form (Scheme and Scheme S1 in the Supporting Information) 17…”

“…These compounds were the result of an onselectiveh omoaldol addition of acetaldehyde, followed by the ketalization of the aldehyde group of the homoaldol adduct by its hydrate form (Scheme 1a nd Scheme S1 in the Supporting Information). [17] We use as uite of modernp ure shift NMR methods based on the homonuclear decoupling band-selective (HOBS) technique [18][19][20][21] in order to obtain fully homodecoupled signals for aset of nonmutually J-coupled protons resonating in aselected region of the 1 Hs pectrum.T he choice of the HOBS over other existing pure shift techniques has been done for various reasons:i )with the aim to maximize sensitivity and to save spectrometer time;i i) the basic set-up is reduced to as imple cali- brationo fas elective1 808 1 Hp ulse according to as elected 1 HNMR region;i ii)HOBS allows af acile implementation into 2D experiments,a ss hown for af amily of HOBS versions of standard 2D HSQC, [18] HSQC-TOCSY,a nd HSQMBC [22] experiments for unambiguous assignment purposes. Additionally,i t is shown here that using ar educed 13 Cs pectralw idth of af ew ppm, optionally combined with nonuniform sampling (NUS), can produce high-resolution 2D HOBS spectra in conventional acquisition times (Figure 1).…”