A derivative of furan-2,3-diol from pandan extract

Abstract

Ahstract-A pandan species, botanically named as Pandanus pygmaues (P. pygmaues) was studied. The chloroform extract of the leaves was fractionated. One pure compound 1 (5 mg) was obtained by using preparative Thin Layer Chromatography (TLC). It gave a purple spot after the TLC plate was sprayed with sulphuric acid (Rr = 0.61, hexane:acetone = 56:44). The molecular structure of 1 was later, determined by Nuclear Magnetic Resonance (NMR) experiments. The chemical shifts of the 1 3 C-NMR spectrum (125 MHz, CDCI3) ranges from oe 29 -147 ppm. This showed the absence of a carbonyl group. In addition, two possible methoxy groups appeared at oe 55.99 and 54.20 ppm. Meanwhile, the ' H-NMR spectrum (500 MHz, CDCI3)showed signals below OR 7.0 ppm only. Yet, it is believed that 1 could be an aromatic compound. Three aromatic protons appeared at OH 6.91 (s), 6.90 (d, J = to Hz) and 6.84 (dd, J = 8 Hz, 2 Hz). A broad singlet at OH 5.63 (hr s) would correspond to a proton involving in a H-C-O-bond. Four aliphatic multiplets (OH 3 -5 ppm) were also detected as a doublet at OH 4.75 (d, J = 4.2 Hz), two double doublets respectively at OH 4.26 (dd, J = 6.7, 9.5 Hz) and OH 3.89 (dd, J = 3.2, 9.5 Hz), and finally a multiplet at OH 3.12 (dd, J = 4.6, 6.7 Hz). The ' H-NMR spectrum also displayed signals at OH 3.91 ppm, supporting the hypothesis for the methoxy groups. It is suggested that respectively one dimethoxyphenyl and oxygenated five-membered ring could be constructed for compound 1-This finding could be considered unusual, in comparison to the common occurrence of pyrrolidinyl-a,fl-unsaturated-y-Iactones from pan dan extracts. In summary, it is concluded that 1 could possibly be a tetrahydro-5-(2,4-dimethoxyphenyl)furan-2,3diol.