Über die Konstitution des Eleutherols. (Inhaltsstoffe aus Eleutherine bulbosa<i>(Mill.) Urb.</i>I)
作者:H. Schmid、Th. M. Meijer、A. Ebnöther
DOI:10.1002/hlca.19500330325
日期:——
Aus den Knollen von Eleutherine bulbosa (Mill.) Urb. wurde ein neuer Pflanzenstoff, das Eleutherol, isoliert. Auf Grund von Abbaureaktionen, deren wichtigste die Alkalispaltung des Naturstoffes in Eleutherolsäure (4-Oxy-5-methoxy-2-naphtoesäure, IV) und Acetaldehyd darstellte, folgt für Eleutherol die Konstitution I. Eleutherol stellt den ersten in der Natur angetroffenen Naphtalidabkömmling dar.
A Rh(II)-catalyzed formal [3+3] cyclization of diazonaphthoquinones and propargyl alcohol is reported to afford 2,3-dihydro-1,4-benzodioxins. Various terminal propargyl alcohols react with diazonapthoquinone in the presence of Rh2(OAc)4 to give the corresponding dihydrodioxins in good to high yields. However, dihydrodioxins are not formed in the reaction of internal propargyl alcohols, and the O–H
The first regio‐ and stereoselective total synthesis of the axially chiral 7,3′‐coupled naphthylisoquinoline alkaloids ancistrocladidine (1) and ancistrotectorine (2) has been described. Both possess a 7,3′‐coupled axis, which before now, was difficult to attain synthetically. Moreover, target 2 has a sensitive relative cis‐array of the two methyl groups at C1 and C3 in the tetrahydroisoquinoline part