Acylated C-21 steroidal bisdesmosidic glycosides from Caraluma umbellata

Novel Steroidal Glycosides from two Indian Caralluma species, C. stalagmifera and C. indica

“…However, we found discrepancies for the 13 C-NMR assignments of Me(19) and Me(21), with Me(19) assigned a higher d value than Me(21) [10]. Our studies with compound 1 along with 2 -4 in this series indicated that these assignments have to be reversed.…”

“…Monobenzoylation of sugar units in saponins is known in carumbelloside IV isolated earlier from Caralluma umbellata, which has a benzoyloxy group at C(2) of the glucose unit attached to C(20) of the aglycon [13]. However, dibenzoylation of vicinal OH groups as found in compounds 6 and 7 has not been reported for steroidal glycosides, to the best of our knowledge.…”

“…Our studies with compound 1 along with 2 -4 in this series indicated that these assignments have to be reversed. To determine the configuration at C(20), we prepared and studied the debenzoylated compound 11, for which 13 C-NMR data in the C and D rings were in very good agreement with data published for sarcostin (= (3b,12b,14b,17a,20S)-pregn-5-ene-3,8,12,14,17,20-hexol) [11]. Hence, the aglycone in compound 1 was identified as (5a)-5,6-dihydrosarcostin 20-benzoate (= (3b,5a,12b,14b,17a,20S)-pregnane-3,8,12,14,17,20-hexol 20-benzoate).…”

“…In addition to the novel compounds 6 and 7, the three known steroidal glycosides carumbelloside III (8), lasianthoside A (9), and lasianthoside B (10) were isolated from the BuOH fraction of C. indica. These compounds were isolated before from C. umbellata [13] and C. lasiantha [12]. C-, and 2D-NMR experiments with Varian-Unity-Inova-600 spectrometer, experimental parameters according to [14], d in ppm, J in Hz.…”

In vitro propagation of Caralluma tuberculata and evaluation of antioxidant potential

“…The genus Caralluma is well studied for presence of variety of pregnane glycosides i.e., russelioside A-D (Al-Yahya et al 2000); russeliosides E-G (AbdelSattar et al 2007); carumbellosides I and II (Lin et al 1994); carumbellosides III, IV and V (Qiu et al 1997); lasianthoside-A and B (Qiu et al 1999); megastigmane glycosides and flavone glycosides 3 and 4 (Bader et al 2003). These phytochemical compounds possess antitumor (Qiu et al 1999); platelet pro-aggregating (Piacente et al 1998); anti-fungal (Hu et al 1999); digitalis receptor binding (Templeton et al 1993); and protect gastric mucosa and have antiulcer properties .…”