Aeridin, a Phenanthropyran derivative from Wattakaka volubilis l. f.

 

K Katkar1, G Mridula2, C Shreedhara2, P Patil3, V Naik1, S Bhamare1, J Vasani1, T Mane1, A Suthar1*and VS Chauhan1

1Piramal Life Sciences Ltd., 1, Nirlon Complex, Off. Western Express Highway, Goregaon (East), Mumbai – 400 063. Maharashtra, India

2Pharmacognosy Deptt., Manipal College of Pharmaceutical Sciences, Manipal University, Manipal, Karnataka, India.

3Pharmaceutical Analysis, Prin. K. M. Kundnani College of Pharmacy, Jote Joy Building, Rambhau Salgaoankar Marg, Cuffe Parade, Mumbai 400 005. India.

 

 

ABSTRACT:

A phenanthropyran derivative 2, 7 – dihydroxy - l, 3 - dimethoxy – 9, 10-dihydrophenanthropyran was isolated from the whole plant of Wattakaka volubilis L. f. The isolation of Aeridin (2, 7 – dihydroxy - l, 3 - dimethoxy – 9, 10-dihydrophenanthropyran) was carried out by column chromatography and reversed phase HPLC and structure was elucidated by 1D and 2D NMR analyses.

 

Fig. 1. Structure of Aeridin              Fig. 2. Some HMBC correlations of Aeridin

 

KEYWORDS: Wattakaka volubilis; 2, 7 – dihydroxy - l, 3 – dimethoxy - 9, 10-dihydrophenanthropyran; Aeridin

 

INTRODUCTION:

Wattakaka volubilis L. f. (Asclepiadaceae) whole plant collected from Sawantwadi, Konkan region of Maharashtra, India in April 2008 and identified by Natural Products - Botany, Piramal Life Sciences Ltd., Mumbai, India, where a voucher specimen is deposited.

 

Uses in traditional medicine

The alcoholic extract of the plant Wattakaka volubilis L. f. (Syn: Dregea volubilis L. f.) is widely used in India as a traditional medicine in the application for boils and abscesses 1. It is also frequently used as a remedy for cough, fever, severe cold, rheumatic pain, diabetes, eye diseases, snake bite etc 2 - 3. The alcoholic extract of the plant is reported to show activity on the central nervous system, as well as anticancer activity against sarcoma 180 in the mice 4.

 

Extraction and Isolation

Dried whole plant was extracted with MeOH at 500 C temperature, and the solvent was evaporated in vacuo. The MeOH extract (30 g) was subjected to column chromatography (CC) on silica gel 230-400 mesh (E. Merck,

 

 

Table 1.  1H NMR and 13C NMR data (300 MHz, CDCl3, J in Hz and δ in ppm)

C

δC

δH

Dept –135

1H–1H COSY

HMBC

1

148.6

 

CQ

 

 

2

122.46

 

CQ

 

 

3

138.0

 

CQ

 

 

4

142.50

 

CQ

 

 

4a

116.85

 

CQ

 

 

4b

101.11

 

CQ

 

 

5

136.21

 

CQ

 

 

5a

62.74

5.2 (2H, s)

- CH2

 

C-2, 3, 4, 6, 7

6

101.62

6.32(1H,dd, J 2.4)

- CH

 

C-7, 8a

7

153.40

 

CQ

 

 

8

107.8                             

6.34 (1H,dd, J 2.1)

- CH

H 9

C-7, 8a

8a

155.68

 

CQ

 

 

9

20.16

2.8 (4H, s)

- CH2

H 8

C-1, 2, 4a, 5, 8a, 10, 10a

10

27.06

2.8 (4H, s)

- CH2

 

C-1, 2, 4a, 5, 8 a, 9, 10a

10a

111.89

 

CQ

 

 

1-OCH3

60.02

3.85 (3H, s)

- CH3

 

C-1

3-OCH3

60.6

3.94 (3H, s)

- CH3

 

C-3

2-OH

 

5.74 (OH, s)

 

 

 

CQ- Quaternary Carbon

 

Germany) using a solvent gradient system (Pet.ether : Acetone) to obtain six fractions. Fraction 5 (550 mg) was then purified by reversed-phase preparative HPLC (Kromosil - C18, 10 m, 250 x 21 mm; ACN - 0.1% TFA; gradient mode – Time / ACN; 0 / 10, 25 / 90, 30 / 90, 32 / 10, 40 / 10; flow rate - 15 ml / min.) to afford 97.3 mg. This is first report of isolation of Aeridin from W. volubilis.

 

Previously isolated classes of constituents

Dredehongbiose, Dregeatriose, 12,13-Epoxy-12, 13-seco-7-multiflorene, Pachybiose, Marsectohexol, Dregeoside H, multiflor-7-en-12a-ol, Volubilol, Volubilogenone, Drevogenin D, Dregeoside Da1, Volubiloside A, Volubiloside B, Drebyssogenin J, Tenasogenin, Dregealol, Drebyssogenin K1, Drevogenin P, Volubiloside C, Hoyacarnoside B. Volubiloside C, Drevogenin B, Drevogenin A, Dregoside A, Drebyssoside 25-8.Newly isolated constituent

 

2, 7 – dihydroxy - l, 3 – dimethoxy - 9, 10-dihydrophenanthropyran9 (1, Fig. 1) (97.3 mg from 1.5 kg of dried material): brown powder; mp 156 °C; UV max (MeOH): 225, 284, 309, 317, 323 nm; IR bands (KBr): 3287, 2943, 2841, 1680, 1615, 1456 and 1433 cm−1; Negative LC-MS: m/z [M-1] −299.1 (100%), 284.1,269.0, 257.1, 242.0; Positive LC-MS: m/z [M+1] − 301.1(100%), 269.1, 237.1, 209.1 (calcd. for C17H16O5, 300.1).

 

Fig. 1. Structure of Aeridin             

 

Fig. 2. Some HMBC correlations of Aeridin

 

ACKNOWLEDGEMENTS:

Special thanks to Natural products – Botany Deptt. for the collection and identification of the plant and the Analytical Sciences, Piramal Life Sciences, for recording IR, LC-MS and NMR spectra.

 

REFERENCES:

1.       Anonymous. The Useful Plants of India; New Delhi-India; Council of Scientific & Industrial Research. 1992; 183.

2.       Muthu C, Ayyanar M, Raja N, Ignacimuthu S. J Ethnobiol Ethnomed 2006; 2: 43.

3.       Prasad PRC, Reddy CS, Raza SH, Dutt CBS.  Fitoterapia 2008; 79: 458.

4.       Anonymous. The Wealth of India, Raw Materials, New Delhi-India; Council of Scientific & Industrial Research, 1976; 6: 564.

5.       Yoshimura S, Narita H, Hayashi K, Mitsuhashi H. Chem Pharm Bul 1983; 31: 3971.

6.       Yoshimura S, Narita H, Hayashi K, Mitsuhashi H. Chem Pharm Bul 1985; 33: 2287.

7.       Sahu NP, Panda N, Mandal N, Banerjee S, Koike K, Nikaid T. Phytochemistry 2002; 61: 383.

8.       Reddy VLN, Ravikanth V, Reddy AVT, Rao TP, Venkateswarlu Y. Tetrahedron Letters 2002; 43: 1307.

9.       Anuradha V, Rao NSP. Phytochemistry 1998; 48 (1): 185.

 

Received on 27.10.2009

Accepted on 13.11.2009     

© A&V Publication all right reserved

Research Journal of Pharmacognosy  and Phytochemistry. 1(3): Nov. – Dec. 2009, 232-233