The volumes of this classic series, now referred to simply as 'Zechmeister' after its founder, L. Zechmeister, have appeared under the Springer Imprint ever since the series' inauguration in 1938. The volumes contain contributions on various topics related to the origin, distribution, chemistry, synthesis, biochemistry, function or use of various classes of naturally occurring substances, ranging from small molecules to biopolymers. Each contribution is written by a recognized authority in his field and provides a comprehensive and up-to-date review of the topic in question. Addressed to biologists, technologists, and chemists alike, the series can be used by the expert as a source of information and literature citations and by the non-expert as a means of orientation in a rapidly developing discipline.

For centuries preparations containing resin from the root of Thapsia garganica L. (Fig. 1) have been used in Arabian and European medicine for treatment of pulmonary diseases, catarrh and as counterirritants for relief of rheumatic pains (1). The properties of the resin were described already by Theophrastos (372-287 B. C. ), Dioscorides (approximately A. D. 50), and Plinius (A. D. 24-79) (2). Radix Thapsiae and Resina Thapsiae have been included in several pharmacopoeias, the latest in the French pharmacopoeia from 1937. The two major active principles were about Fig. I. Thapsia garganica References, pp. 163-167 Sesquiterpenoids from Thapsia Species 131 Thapsigargin (1), Rl: Oct, R2= But Thapsigargicin (2), Rl= Hex, R2 = But Thapsitranstagin (3), Rl: iVai, R2= 2-MeBut Thapsivillosin A (4), Rl= Ang, R2= Sen Thapsivillosin B ( 5), Rl: Ang, R2= 2-MeBut Thapsivillosin C ( 6), Rl= Oct, R2= 2-MeBut Thapsivillosin D ( 7), Rl: 6-MeOct, R2= Sen Thapsivillosin E ( 8), Rl: 6-MeOct, R2= 2-MeBut Thapsivillosin G ( 9), Rl= 6-MeHcp, R2= 2-MeBut Thapsivillosin H ( 10), Rl or R2= Ang or Sen Thapsivillosin I ( 11), Rl= Ang, R2= But Thapsivillosin J ( 12), Rl: iVai, R2= But Thapsivillosin K ( 13), Rl: Sen, R2= 2-MeBut Chart 1. Hexaoxygenated thapsigargins found in Thapsia two decades ago found to be the sesquiterpene lactones thapsigargin (1) and thapsigargicin (2) (3).