Poisonous Plants of India

Abstract

(IH, d, J = 7 Hz, H-3), 6.71 (IH, d, J = 2 Hz, H-8), 7.01 (1H. d, J = 2 Hz, H-6), 7.84 (lH, d, J = 7 Hz, H-2). 5-Methoxy-7-hydroxychromone @CL 5,7-Dihydroxy-chromone (200 mg), PhCH&I (0.13 ml) and K&O, (300 mg) in dry Me*CO (200 ml) were refluxed for 8 hr to give 2e: colourless needles from EtOAc-petrol, mp 141-142". 'H NMR (S, CDCII): 5.08 (2H, s,-Om,Ph), 6.15 (lH, d, J =7Hz, H-3), 6.4 (2H, s, H-6, H-8), 7.35 (SH, m,-OCH*Ph), 7.67 (IH, d, J = 7 HZ, H-2), 12.64 (IH, s, OH-5). Methylzion of 2e gave 2f: colourless needles from CHCi,-petrol, mp 170-171". 'H NMR (8, CDCI,): 3.9 (3H, s,-OMe), 5.07 (2H, s,-Oa,Ph), 6.14(lH, d, J = 7 Hz, H-3), 6.45 (2H, m, H-6, H-8), 7.35 (SH. m,-OCH,fi), 7.54 (lH, d, J = 7 Hz, H-2). Debenzylation of 2f (IOOmg) with HCI (0.5 ml) in HOAc (3 ml) afforded 7-hydroxy-5-methoxychromone (2~) which crystallized from EtOAc-petrol as colourless needles (SO mg), mp 218-220". Key Word Index-Hydrocotyle sibthorpioides; Umbelliferae; quercetin 3-galactoside; isorhamnetin; quer-cetin 3-(6"-caffeoylgalactoside). Abstract-In addition to quercetin, quercetin 3-galactoside and isorhamnetin, a new caffeoylgalactoside has been isolated from Hydrocotyle sibthorpioides