Phytochemisrry, Vol. 28, No. 11, pp. 3227-3229, 1989. 003l-9422/89 $3.00 + 0.00 Printedin Great Britain. PergamonPress plc SHORT REPORTS TWO IRIDOID GLUCOSIDE ESTERS FROM ANARRHZNUM ORIENTALE A. M. DAWIDAR, S. T. ESMIRLY, A. S. M. AL-HAJAR, J. JAKUPOVIC* and M. ABDEL-MOGIB* Chemistry Dept., Faculty of Science, King Abdulaziz University, Jeddah, K.S.A.; *Institute for Organic Chemistry, Technical University of Berlin, D-1000 Berlin 12, F.R.G. (Received in revised firm 3 April 1989) Key Word Index--Anarrhinum orient&, Scrophulariaceae; 6-0-nerol-8-oyl-antirrinoside; 6’-O-cinnamoyl-antirrin- oside. Abstract-Two new iridoid glucoside esters were isolated from Anarrhinum orientale and identified by spectral methods as 6-O-nerol-8-oyl-antirrinoside and 6’-0-cinnamoyl-antirrinoside. INTRODUCTION structural link between terpenes and alkaloids [2] and display an interesting spectrum of biological activity [3]. Iridoid glucosides are common in the Scrophulariaceae Anarrhinum orientale Benth (Scrophulariaceae) is used and related families, their presence being considered as a in the traditional medicine in Al-Baha region (in KSA) as valuable systematic character [ 11. Iridoid glucosides an antidiabetic. We wish to report the isolation and occupy an important position in the field of natural structure elucidation of two new iridoid glucoside esters products chemistry and biology since they provide a from this plant. Table 1. ‘H NMR spectral data of compounds 1 *, 1Act and 2* (400 MHz, dvalues) H 1 1Ac 2 A& 1 3 4 6 7 9 10 Glc 1’ 2 3 4 5 6 OR 1” 2” 4” 5” 6” 9” lo” OH OAc 5.42 (5.8) d 6.37 (6.2) d 4.90 (6.2) br d 4.83 (2.2) d 3.50 (2.2) d 2.55 (5.8) br d 1.44 s 4.62 (8) d 3.32 m 3.48 m 3.48 m 3.32 m 3.84 (12.5, 2.5) dd 3.78 (12.5, 4) dd 4.06 (7) br d 5.41 (7) br t 2.20 (7) br t 2.32 (7, 7) br dt 6.84 (7, 1.5) tq 1.83 (1.5, 1) dt 1.71 (1, 1) dt 5.10 (8.2) d 6.29 (6.2) d 4.95 (6.2) d 5.04 (1.5) d 3.54 br s 2.48 (8.2) br d 1.50 s 4.93 (8) d 5.03 (8, 9.5) dd 5.24 (9.5, 9.5) dd 5.10 (9.5, 9.5) dd 3.72 (2.5, 4.5, 9.5) ddd 4.26 (12.5, 4.5) dd 4.19 (12.5, 2.5) dd 4.55 (7) br d 5.39 (7) br t 2.30 (7) br t 2.20 m 6.86 (7, 1.5) tq 1.86 br s 1.77 br s 2.20 br s 2.08 s 2.04 s 2.03 s 2.02 s 2.00 s 5.22 (5) d 6.26 (6.2) d 4.72 (6.2) br d 3.70 (2.5) d 3.30 (2.5) br d 2.32(5) br d 1.30s 4.53 (8) d 3.34 In 3.20 m 3.34 m 3.44 m 4.41 (12.5, 2.5) dd 4.34 (12.5,4.5) dd 7.58 (16) d 6.35 (16) d 7.41 m 7.27 m *In CDCl,-CD,OD mixture (400 MHz). tin CDCl, (400 MHz). 3227