Indian Journal of Chemistry Vol. 44B, May 2005, pp 1088-1091 New triterpenic esters of oleanene-series from the flowers of Calendula officinalis Linn. T Naved, S H Ansari*, H M Mukhtar & M Ali Department of Pharmacognosy and Phytochemistry, Faculty of Pharmacy, Jamia Hamdard (Hamdard University), Hamdard Nagar, New Delhi 110 062 E-mail: shansari189@rediffmail.com Received 19 November 2003; accepted (revised) 6 May 2004 One new triterpenoid of oleanene-series, cornulacic acid acetate 1 along with oleanolic acid acetate has been isolated from the flowers of Calendula officinalis Linn. The structure of 1 has been established as 3β-acetoxy-olean-12-ene-27-oic acid on the basis of spectral data analysis and chemical reactions. IPC: Int.Cl. 7 A 61 K 35/00 The genus Calendula includes 15 species, native of Central Europe and the Mediterranean region 1 . Calendula officinalis Linn (Asteraceae), commonly known as marigold, is one of the most well-known and versatile herbs in the western medicine 2 . It is an aromatic, erect, annual herb, up to 1.5 m in height, commonly cultivated in India 3 . The bright orange petals are an excellent remedy for inflammation and skin diseases, their antiseptic and healing properties help to prevent the infection and speed up the rate of repair 4 . The decoction of the flowers is taken orally to cure measles, smallpox and the expressed fresh juice as a remedy against costiveness, jaundice, wounds, ulcers, skin diseases, suppression of monthly flow 3,4 , fevers, to promote perspiration and to prevent suppuration 5 . Infusion of C. officinalis is used in anemia and as an ointment for sores, cuts, bruises and cracks in hands 6 . The flowers contain calenduline, oleanolic acid glycosides of 3-glucuroside and sterol glycosides, pentacyclic triterpenes and a red dye 7 . This paper describes the isolation and characterization of cornulacic acid acetate 1 and oleanolic acid acetate from the flowers of the plant grown in Delhi. Results and Discussion Cornulacic acid acetate 1 responded positively to Liebermann-Burchard test and yielded effervescence with sodium bicarbonate solution. Its IR spectrum exhibited absorption bands for carboxylic (3250, 1690 cm -1 ), ester (1725 cm -1 ) and unsaturation (1640 cm -1 ) functions. Its EIMS showed molecular ion peak at m/z 498 corresponding to a pentacyclic triterpenoid of formula C 32 H 50 O 4 . It indicated eight degrees of unsaturation, five of them were adjusted in a pentacyclic triterpenic carbon framework and one each in olefenic linkage, ester and carboxylic groups linkage. The mass spectrum of 1 was distinctive of pentacyclic triterpenes of amyrin series in which rings A, B, D and E were saturated. The mass ion peaks at m/z 250 and 248 were generated by retro-Diels Alder fragmentation pattern of ring C characteristic to Δ 12 amyrins 8 . The mass spectrum displayed other ion fragments at m/z 190 [250-AcOH] + , 175 [190-Me] + , 160 [175-Me] + , 203 [248-CO 2 H] + , 233 [248-Me] + , 189 [233-CO 2 ] + , 438 [498-AcOH] + , 423 [438-Me] + , 454 [498-CO 2 ] + , 439 [452-Me] + , 422 [437-Me] + and 396 [452-Ac] + suggesting the existence of the acetoxy group in rings A or B and an angular carboxylic group in rings D or E. The 1 H NMR spectrum of 1 displayed a one-proton downfield broad signal at δ 5.27 assigned to vinylic C-12 proton. A one-proton double doublet at δ 4.49 1 AcO H H H COOH H