Crystal structure of 1,1′-disinomenine tetrahydrate, C38H44N2O8 · 4H2O

Abstract

Source of materialSinomenine is the main pharmacologically active alkaloid in the traditional Chinese plant medicine of Sinomenium acutum.Itwas produced from the powder of the plant roots by the BaojiYongjia Plant Medicine Extracting Limited Company, Baoji, P. R. China, under the patent technology [1], and crystallized from the concentratedb enzene extract of thep owder. Ther emaining sticky mother liquor (3 kg) after the extraction of sinomenine was obtained from the company. Thesticky residue was fractionated by columnchromatography on silica gel (100 mesh) eluted gradually with chloroform to chloroform/methanol (30:1; 10:1 and 4:1) to afford 7fractions, QT1 to QT7.The QT4 (5.5 g) was subjected to columnchromatography on silica gel (300-400 mesh) eluted with chloroform/methanol (20:1 to 5:1) to give 7s ubfractions, QT4-1 to QT4-7. The QT4-6 was crystallized repeatedly from methanol to yield the colorless crystals of the title compound (25 mg) suitable for single crystal X-ray diffraction analysis at room temperature. Experimental detailsOnly theeight Hatoms from four crystalwater molecules have been refined; they were determined from Fouriermap.All other Hatoms attached to Catoms and Oatoms of the title compound molecule were calculated by theoretical method and were not refined. The Flack parameter was 0(10). Discussion S. acutum is distributed mainly in hilly regions of southwest, northwest and southeast China. The dried stemsand roots of the planta re at raditional Chinesem edicine to cure rheumatism, arthralgia,dropsyand dermatophytosisrecordedinthe Chinese Pharmacopoeia [2]. The plant is ar ich source of alkaloids of bisbenzylisoquinoline, aporphine, isoaporphine, protoberberine and morphinane types. The diversity of the alkaloids and activities of this medicinal plant motivated our research work, we have studied the remaining mother benzene liquor of roots of S. acutum and obtained nearly 20 alkaloidal compounds, including the title compound. We once obtained them as the amorphous powder from thestems of thesameplant [3]. We have already reported thei solation andc rystal structureso fc heilanthifoline [ 4], 8-oxotetrahydropalmatine [5], tetrahydroepiberberine [6],8 -oxocanadine [7], sinoacutine [8], 8-demethoxyrunanine [9,10], sinoracutine [11,12], N-formylanonaine [13] and two new morphinane alkaloid dimers [3]. The title compound disinomenine tetrahydrate is ad imer of sinomenine, in which the two monomers are interconnected at C1 position. The two benzene rings from each monomer are perpendicular to each other in order to decrease the steric hindrance. Each monomer is composed of rings A, B, Cand D. The two methoxy groups at each C3 are basically coplanar to their attached benzene rings A, the rings Band Cadopt half-chair conformations whereas the rings Dadopt chair conformations. Z. Kristallogr. NCS 227 (2012) 93-95