108 research outputs found
A second polymorph of β-arteether
The crystal structure of the title compound, C17H28O5, reported here is a polymorph of the structure first reported by El-Feraly, Al-Yahya, Orabi, McPhail & McPhail [J. Nat. Prod. (1992). 55, 878–883]. It is a derivative of the antimalaria compound artemisinin and consists primarily of three substituted ring systems fused together. A cyclohexane ring (distorted chair conformation) fused to a tetrahydropyran group (distorted chair) is adjacent to an oxacycloheptane unit containing an endo-peroxide bridge, giving the molecule its particular three-dimensional arrangement. The crystal packing is stabilized by intermolecular C—H⋯O interactions between an O atom from the endo-peroxide bridge and H atoms from both the cyclohexane and seven-membered oxacycloheptane fused rings, as well as between an O atom and H atom from adjacent tetrahydropyran rings. The two polymorphs have the same space group and similar cell parameters for the a and b axes, but significantly different values for the c axis
ChemInform Abstract: SYNTHESIS AND CARBON-13 NUCLEAR MAGNETIC RESONANCE ASSIGNMENTS OF XENOGNOSIN
ChemInform Abstract: BIOGENIC-TYPE SYNTHESIS OF SANTONIN, CHRYSANOLIDE, DIHYDROCHRYSANOLIDE, TULIRINOL, ARBUSCULIN-C, TANACETIN, AND ARTEMIN
Selection and micropropagation of high artemisinin producing clones ofArtemisia annua L.
Effect of Khatamines and Their Enantiomers on Plasma Triiodothyronine and Thyroxine Levels in Normal Wistar Rats
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