ChemInform Abstract: FORMATION OF A SPIRO COMPOUND BY HEATING β‐CYCLOFARNESYLIC ACID CHLORIDE

Abstract

Beim Erhitzen des Säurechlorids (I) mit Triethylamin bildet sich das Dimerisierungsprodukt (II) des durch HCl‐Abspaltung entstandenen Ketens.

Carotenoids and polyterpenoids

“…This synthetic work led to revision of the absolute configurations that had previously been assigned to mactraxanthin pared by a biomimetic route, involving concerted hydroxyprenylation-cyclization of a C, or C, acyclic precursor of the e n d -g r ~u p . ~~ Selective rearrangement of 5,6,5',6'-diepoxy-5,6,5',6'-tetrahydro-r),p-carotene (60) in diethyl ether that contained malonic acid gave a mixture of the 8'-epimeric luteoc hromes [ 5,6,5',8'-diepoxy-5,6,5', 8'tetrahydro-P,P-carotenes] (61) and (62). 40 The preparation of the pyridinium carotene analogue (63) as a potential antitumour agent has been de~cribed.~' Further work on the preparation and properties of carotenoporphyrin-quinone structures such as (67)…”