1 research outputs found
Isolation and Identification of Two Novel Condensed Aromatic Lactones from Zhundong Subbituminous Coal
Zhundong subbituminous coal was extracted
with isometric carbon
disulfide (CDS) and acetone mixed solvent (IMCDSAMS) to obtain the
extract (E<sub>M</sub>). E<sub>M</sub> was fractionated with petroleum
ether (PE), CDS, methanol, acetone, IMCDSAMS, and tetrahydrofuran
to obtain the sub-extracts 1–6 (E<sub>S1</sub>–E<sub>S6</sub>), respectively. E<sub>S2</sub> was sequentially eluted with
PE and 30, 50, and 70% CDS/PE mixed solvents through a silica-gel-packed
column to obtain eluted fractions 1–4 (EF<sub>1</sub>–EF<sub>4</sub>). A series of condensed aromatic lactones (CALs) were detected
in EF<sub>4</sub>. Among them, 5<i>H</i>-phenanthroÂ[1,10,9-<i>cde</i>]Âchromen-5-one and 4<i>H</i>-benzoÂ[5,10]ÂanthraÂ[1,9,8-<i>cdef</i>]Âchromen-4-one were further isolated as nearly pure
compounds by gelatin column chromatography and identified by gas chromatography/mass
spectrometry, atmospheric solid analysis probe/time-of-flight mass
spectrometry, Fourier transform infrared spectrometry, <sup>1</sup>H nuclear magnetic resonance spectrometry, and <sup>1</sup>H–<sup>1</sup>H correlation spectrometry. Main fragmental ions in the mass
spectrum of each CAL are formed by successive losses of <i>m</i>/<i>z</i> 28 (CO) and 29 (−CHO) from the molecular
ion. An effective way to isolate CALs from low-rank coals was provided
in this paper