126191-23-9Relevant academic research and scientific papers
Syntheses of Combretastatins D-1, D-2, and D-4 via Ring Contraction by Flash Vacuum Pyrolysis
Harras, Marina,Milius, Wolfgang,Aitken, R. Alan,Schobert, Rainer
, p. 579 - 587 (2017/04/26)
We report the syntheses of combretastatins D-2 and D-4 as well as a formal synthesis of combretastatin D-1 by a conceptually new route harnessing a ring-contracting flash vacuum pyrolytic extrusion of sulfur dioxide from the respective 16-membered sulfone precursors. Via flash vacuum pyrolysis, even metaparacyclophanes as small and strained as the hitherto unknown oxa[1.5]metaparacyclophane could be prepared as a side product en route to combretastatin D-2 by synchronous extrusion of SO2 and CO2.
Antineoplastic agents. 565. Synthesis of combretastatin D-2 phosphate and dihydro-combretastatin D-2
Pettit, George R.,Quistorf, Peter D.,Fry, Jeremy A.,Herald, Delbert L.,Hamel, Ernest,Chapuis, Jean-Charles
scheme or table, p. 876 - 883 (2009/12/26)
A modified synthetic route to combretastatin D-2 (5) was devised in order to further evaluate its biological activity, for its conversion to phosphate prodrugs (25-28), and as a route to obtaining dihydro-combretastatin D-2 (42). A parallel first total synthesis of dihydro-combretastatin D-2 was completed, proceeding from a saturated 3-phenylpropionic ester intermediate via the Ullmann biaryl ether reaction (39-41). In contrast to the cancer cell growth inhibitory activity exhibited by combretastatin D-2, relatively minor structural modifications (41, 42) caused elimination of those properties.
Total synthesis of combretastatins D
Couladouros, Elias A.,Soufli, Ioanna C.,Moutsos, Vassilios I.,Chadha, Raj K.
, p. 33 - 43 (2007/10/03)
The 15-membered caffrane ring of the natural product group of combretastatins D is synthesized in high yield with suitably functionalized saturated seco acids. The key step is a Mitsunobu-type macrolactonization. A common synthon is used for the construct
Synthesis of (±)-combretastatin D-1 and combretastatin D-2
Rychnovsky,Hwang
, p. 5414 - 5418 (2007/10/02)
(±)-Combretastatin D-1 was synthesized in 16 steps by way of its congener, combretastatin D-2. In the key step, the strained 15-membered lactone ring was formed using high-dilution Mitsunobu conditions in 89% yield. Saturated seco acid 4 was a much better substrate for the cyclization reaction than the unsaturated seco acid 3.
Total Synthesis of Combretastatin D-2: Intramolecular Ullmann Macrocyclization Reaction
Boger, Dale L.,Sakya, Subas M.,Yohannes, Daniel
, p. 4204 - 4207 (2007/10/02)
The total synthesis of combretastatin D-2, a cytotoxic constituent of Combretum caffrum (Combretaceae), is detailed and is based on the implementation of a key intramolecular Ullmann macrocyclization reaction for formation of the cyclic 15-membered caffra
