New bioactive heptenes from melodorum fruticosum (annonaceae)

Unusual metabolites from some Tanzanian indigenous plant species

“…S. gracilis ssp. gracilis we isolated the two cytotoxic heptane derivatives (+)-melodorinol (10) and (+)-acetylmelodorinol (11), together with the corresponding diol precursor (+)-5-(2,3-dihydroxy-propylidene)-5H-furan-2-one (12) [26] that was previously prepared from (+)-glyceraldehyde as an intermediate toward the synthesis of (+)-acetylmelodorinol [27]. More recently, another Annonaceae species, C. kirkii, yielded several heptenolides including (+)-acetylmelodorinol, (+)-5-(2,3-dihydroxy-propylidene)-5H-furan-2-one, and (+)-benzoylmelodorinol (13) [12,28,29].…”

Synthesis of revised structure of klaivanolide (acetylmelodorinol)

“…[11][12][13][17][18][19][20][21] All the spectral data was compared with published data and found to be identical. [11][12][13][17][18][19][20][21] The compounds cismelodorinol (5) and trans-melodorinol (6) were subjected to acetylation to give corresponding acetylmelodorinol 2 and its trans-isomer 7, respectively. All the spectral data of the synthetic racemic acetylmelodorinol 2 is in complete agreement with the literature reports.…”

Synthesis of New Bis-Iminodihydrofurans

“…Infrared (IR) spectra were recorded on a Specord 75 IR spectrometer (Analytik Jena AG, Jena, Germany). Proton ( 1 H) nuclear magnetic resonance (NMR) spectra were recorded at 300 MHz on a Varian Mercury 300 VX spectrometer (Palo Alto, CA, USA) with dimethyl sulfoxide (DMSO)-d 6 and DMSO-d 6 :carbon tetrachloride (CCl 4 ), 1:3 (v/v) as solvent and tetramethylsilane (TMS) as internal standard. Monitoring of the reaction course and the purity of the products was carried out by thin layer chromatography (TLC), on silufol UV254 plates, eluent acetone:benzene 1:2 (v/v) and visualized using iodine vapor.…”

“…2-Oxo-2,5-dihydrofuran subunit has been found both in several bioactive natural (ascorbic, penicillic and tetronic acids), synthetic products [1][2][3][4][5][6][7][8][9][10][11] and in a number of drugs with diverse biological activities, such as antifungal, antibacterial and anti-inflammatory.…”