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- Spectroscopic data of some selected compounds are given below: 4: Crystalline, m. p. 198-200[ddot]; MS(FAB): m/z 390 (M++1), 412 (M++Na); IR(KBr): δNH str=3432 cm−1; [a]D = −71.28 (C=0.10 in H2O); 1H NMR (400 MHz, D2O) : δ7.38 (s, 1H, H-3), 5.20 (d, 3, 1H, H-1), 4.68 (d, 6, 1H, H-1′), 4.95 (m, 1H, H-7), 3.56 (s, 3H, OCH3), 3.30 (te, 1H, H-3′), 3.27 (me, 1H, H-5′), 3.12 (te, 1H, H-4′), 3.10 (te, 1H, H-2′), 2.90 (me, 2H, H-5 and H-6′α), 2.61 (m, 1H, H-6′β), 1.98 (me, 2H, H-6α& H-9), 1.73 (m, 1H, H-8), 1.55 (m, 1H, H-6β), 0.89 (d, 6.9, 3H, H-10); 13C NMR (100 MHz, D2O): δ170.07 (C-11), 150.97 (C-3), 113.21 (C-4), 98.98 (C-1′), 97.87 (C-1), 76.45 (C-5′), 75.71 (C-7′), 74.27 (C-3′), 72.89 (C-4′), 71.28 (C-2′), 51.89 (OCH3), 45.16 (C-9), 41.62 (C-6′), 40.47 (C-6), 40.23 (C-8), 29.94 (C-5), 12.07 (C-10). Analysis calculated for C17H27 O9N: C, 52.44; H, 7.03 and N, 3.59, Found: C, 52.25; H, 7.06, N, 3.23. 5: Crystalline m. p. 188-190[ddot]; MS(FAB): m/z 373 (M+ +1), 395 (M++Na); [a]D= −154.28 (C=0.10 in CH3OH); 1H NMR (400 MHz, D2O): δ7.38(s, 1H, H-3), 5.27(d, 6, 1H, H-1), 5.20 (d, < 2, 1H, H-1′), 4.31 (te, 1H, H-5′), 4.29 (te' 1H, H-4′), 4.17 (d, 12, 1H, H-6′β), 4.13 (t, 6, 1H, H-3′), 4.09 (m, 1H, H-7), 3.96 (dd, 9,3,1H, H-6′δ), 3.71 (te, 1H, H-2′), 3.70 (se, 3H, OCH3), 3.08 (m, 1H, H-5), 3.45 (m, 1H, H-6α) 2.03 (m, 1H, H-9), 1.85 (m, 1H, H-8), 1.62 (ddd, 18,12,6,1H, H-6β), 1.10 (d, 8, 3H, H-10); 13C NMR (100 MHz, D2O): δ166.74 (C-11), 150.17 (C-3), 112.25 (C-4), 98.26 (C-1), 95.54 (C-1′), 73.94 (C-7), 72.15 (C-5′), 72.06 (C-2′), 71.51 (C-3′), 70.13 (C-6′), 69.39 (C-4′), 50.82 (OCH3), 44.80 (C-9), 41.75 (C-6), 40.41 (C-8), 30.67 (C-5), 13.11 (C-10). Analysis calculated for C17O9H24: C, 54.83; H, 6.45, Found: C, 54.47; H, 6.18. 10: Crystalline, m. p. 99-101[ddot]; MS (FAB): m/z 543 (M++1), 565 (M++Na); [a]D= −70.67 (C=0.14 in CHCl3); 1H NMR (400 MHz, CDCl3): δ7.31 (s, 1H, H-3), 5.23 (d, 2, 1H, H-1), 5.22 (te, 1H, H-4′), 5.16 (me, 1H, H-7), 4.96 (t, 12, 1H, H-4′), 4.85 (te, 1H, H-2′), 4.84 (de, 8, 1H, H-1′), 3.69 (s, 3H, OCH3), 3.51 (m, 1H, H-5′), 3.02 (m, 1H, H-5), 2.24 (m, 1H, H-6α), 2.06, 2.04, 2.02, 1.90 (s's, 3H each, 4×OCOCH3), 2.05 (me, 1H, H-9), 1.95 (me, 1H, H-8), 1.80 (me, 1H, H-6β), 1.25 (d, 6, 3H, H-6′), 1.02 (d, 7, 3H, H-10); 13C NMR (100 MHz, D2O): δ 170.55, 170.14, 169.56, 169.08, 167.03 (5×C=O), 149.13 (C-3), 113.36 (C-4), 95.59 (C-1′), 94.46 (C-1), 77.08 (C-7), 73.14 (C-3′), 72.38 (C-4′), 70.95 (C-2′), 70.29 (C-5′), 51.14 (OCH3), 45.42 (C-9), 38.72 (C-8 & C-6′), 29.73(C-5), 20.96, 20.54e, 20.09 (4×OCOCH3), 17.21 (C-6′), 12.32 (C-10). Analysis calculated for C25H24O13: C, 55.35; H, 6.27 Found: C, 55.12; H, 6.33. 12: Viscous mass; MS (FAB): m/z 373 (M++1), 395 (M++Na); [a]D= −67.34 (C=0.10 in CH3COCH3); 1H NMR (300 MHz, Acetone-d6): δ7.30 (d, 0.89, 1H, H-3), 5.14 (d, 4.7, 1H, H-1), 4.80 (d, 5.6 1H, H-1′), 5.69 (d, 2.6, 2H, H-6′α), 4.59 (d, 1.7, 2H, H-6′β), 4.01 (me, 1H, H-7), 3.97 (te, 1H, H-3′), 3.62(s, 3H,OCH3), 3.46(t,6.5, 1H, H-2′), 3.37 (t, 8.5, 1H, H-3′), 3.05 (m, 1H, H-5), 2.21 (dd, 15.5, 7.8, 1H, H-α), 1.95 (m, 1H, H-8), 1.82 (m, 1H, H-9), 1.52 (m, 1H, H-6β), 1.06 (d, 6.8, 3H, H-10); 13C NMR (100 MHz, Acetone-d6): δ 167.77 (C-11), 158.38 (C-5′), 150.84 (C-3), 113.79 (C-4), 100.74 (C-1′), 97.30 (C-1), 93.96 (C-6′), 76.41 (C-3′), 74.52 (C-7), 73.97 (C-2′), 71.15 (C-4′), 51.18 (OCH3), 94.95 (C-9), 42.53 (C-6), 41.80 (C-8), 31.86 (C-5), 13.49 (C-10). Analysis calculated for C17H24O9: C, 54.29; H, 6.34, Found: C, 54.83; H, 6.45. 13: Crystalline, m. p. 83-85[ddot]; MS(FAB): m/z 617 (M++1), 639 (M++Na); [a]D= −62.80 (C=0.12 in CHCl3); 1H NMR (400 MHz, CDCl3): δ7.26 (s, 1H, H-3), 5.17 (me, 3H, H-1, H-7 & H-3′), 4.98 (te, 9, 1H, H-2′), 4.95 (te, 9, 1H, H-4′), 4.80 (d, 9, 1H, H-1′), 3.69 (se, 3H, OCH3), 3.65 (me, 1H, H-5′), 3.18 (ddd, 18, 6, 3, 2H, H-6′), 3.00 (m, 1H, H-5), 2.37 (s, 3H, SCOCH3), 2.27 (dd, 6,3, 1H, H-6α), 2.20 (m, 1H, H-9), 2.10, 2.05, 2.01 & 1.90 (s',s, 3H each, 4×OCOCH3), 1.95 (m, 1H, H-8), 1.80 (m, 1H, H-6β), 1.05 (d, 8, 3H, H-10); 13C NMR (100 MHz, CDCl3):δ 194.10 (SCOCH3), 170.31, 169.43e, 168.82 (4×OCOCH3), 166.04 (C-11), 149.10 (C-3), 113.17 (C-4), 95.65 (C-1′), 94.75 (C-1)Ø, 76.70 (C-7), 73.02 (C-5′), 72.10 (C-2′), 70.56 (C-3′), 70.36 (C-4′), 50.90 (OCH3), 45.35 (C-9), 30.72 (C-8), 30.72 (C-6), 30.15 (C-5), 29.01 (C-6′), 29.01 (SCOCH3), 20.80, 20.41, 20.31, 19.93 (4×OCOCH3), 12.27 (C-10). Analysis calculated for C27H36O14S: C, 52.59; H, 5.86; Found C, 52,.65; H, 5.96. [where e denotes overlapping with other signals].