MEXICAN MEDICINAL PLANTS XXIX THREE NEW DITERPENE QUINONES FROMSALVIA BALLOTAEFLORA

Abstract

From the aereal part of S a 1 v i a b a 11 o t a e f 1 o r a , BENTH (Lanziaceae) three new diterpene quinones were isolated, all with an abietane skeleton. One of them, romulogarzone is an o r t h oquinone, the other two, conacytone and icetzxone are pa r aquinones, their structures were elucidated on chemical and physical data.

Absolute configuration of the diterpenoids icetexone and conacytone from Salvia ballotaeflora

“…The structure was verified by single‐crystal X‐ray diffraction analysis for which the unit cell parameters agree with those published in 1976, thereby establishing the identity of 1 from both natural and synthetic origins, although the original X‐ray paper seems to be overlooked for such a comparison . It is clear from the asymmetric synthesis that icetexone is properly represented as shown in 1 , but it might be inferred that the natural occurring diterpenoid would be the enantiomer since for synthetic 1 [α] D −70, in chloroform, is reported, while for the natural sample [α] D +33.3, also in chloroform, is given …”

“…In summary, the absolute configuration of natural occurring icetexone ( 1 ) and conacytone ( 3 ) is not rigorously proven, and their NMR data remain to be assigned. Therefore, in the present paper, we describe a full account regarding the three terpenoids 1 , 3 , and 5 originally reported in 1976.…”

“…The structure and relative stereochemistry of 1 followed from single‐crystal X‐ray diffraction analyses, whose data allowed to refine the structure to R = 3.7%. Another paper further describes a third compound, romulogarzone, which is postulated as the ortho ‐quinone 5 without rigorous structure proof either by X‐ray analysis or by chemical correlation of 1 and 5 through a common leucotriacetate derivative, if as a prerequisite 1 and 5 would show depression in a mixed melting point determination. The structure of 3 also followed from X‐ray data, while for 5 , no further isolation report is available since then.…”

“…The structure of 3 also followed from X‐ray data, while for 5 , no further isolation report is available since then. Icetexone ( 1 ) appeared also in Salvia anastomosans , Salvia candicans , and Salvia pubescens …”

PHYTOGEOGRAPHICAL SIGNIFICANCE OF THE OCCURRENCE OF ABIETANE‐TYPE DITERPENOIDS IN SALVIA SECT. ERYTHROSTACHYS (LAMIACEAE)

“…The only other section of Salvia subgenus Calosphace that has yielded abietane derived diterpenoid is S. sect. Tomentellae (Dominguez et al, 1976;Rodriguez-Hahn et al, 1986). These findings are interesting phytogeographically because European and Asiatic saIvias studied (Hassan et al, 1986;Fraga et al, 1986;Patudin et al, 1974;Hueso-Rodriguez et al, 1983) are characterized by similar abietane-type diterpenoids.…”