10154-05-9Relevant articles and documents
SUPERACID CYCLIZATION OF ESTERS OF SOME BISHOMOISOPRENOID ACIDS
Ungur, N. D.,Tuen, Nguen Van,Popa, N. P.,Vlad, P. F.
, p. 561 - 568 (1992)
It is shown that on the superacid cyclization of esters of bishomobicyclogeranylgeranic and E,E-bishomofarnesic acids fully cyclized hydroxyesters are formed in good yield, while on the interaction of esters of 6-hydroxy- and 6-acyloxy-15-bishomobicyclogeranylgeranic acids with a superacid no carbocyclization takes place.
Synthesis of rac-hippospongic acid A and revision of the structure
Tokumasu, Munetaka,Ando, Hiroshi,Hiraga, Yoshikazu,Kojima, Satoshi,Ohkata, Katsuo
, p. 489 - 496 (2007/10/03)
rac-Hippospongic acid A of the reported structure 1 and the revised structure 2 were synthesized. The synthetic strategy of these compounds consists of homologation of (2E,6E,10E)-geranylgeraniol and (2E,6E)-farnesol, respectively, Wadsworth-Emmons reaction, and cyclization to form the tetrahydropyran ring bearing an α-methylene group on the carboxylic moiety. Spectral comparisons of the synthetic compounds 1,2 and the natural product suggested that hippospongic acid A bears the structure of 2.
Stereoselective syntheses of (+)-rhopaloic acid A and (-)-ent- and (±)-rac-rhopaloic acid A
Takagi, Ryukichi,Sasaoka, Asami,Nishitani, Hiroko,Kojima, Satoshi,Hiraga, Yoshikazu,Ohkata, Katsuo
, p. 925 - 934 (2007/10/03)
Rhopaloic acid A (+)-1 and the related compounds (-)-ent-1 and (±)-rac-1 have been stereoselectively synthesized. The synthetic strategy consists of successive homologation of (2E,6E)-farnesol 7 and cyclization to form a tetrahydropyran ring, together wit
Synthesis of norsesterterpene rac- and ent-rhopaloic acid A
Takagi, Ryukichi,Sasaoka, Asami,Kojima, Satoshi,Ohkata, Katsuo
, p. 1887 - 1888 (2007/10/03)
The stereoselective synthesis of rac- and ent-rhopaloic acid A 1 has been accomplished, via successive homologation of (2E,6E)-farnesol 2 and cyclization to form a tetrahydropyran ring, together with final introduction of an α-methylene group; the asymmet
Stereochemical Studies on Porphyrin a: Assignment of the Absolute Configuration of a Model Porphyrin by Degradation
Battersby, Alan R.,Cardwell, Kevin S.,Leeper, Finian J.
, p. 1565 - 1580 (2007/10/02)
The synthesis is described of a porphyrin alcohol (22) which has a structure very similar to that of porphyrin a (2).The model porphyrin was resolved by separation of its camphanate esters.Ozonolysis of the 2-nitrobenzoate of each enantiomer in tritiated form gave a derivative of 2-hydroxypentadioic acid whose configuration was determined by dilution analysis.It is demonstrated that correlation of the stereochemistry of porphyrin a with that of the model (22) will be possible by means of the (1)H and (19)F n.m.r. spectra of the corresponding esters with (-)-3,3,3-trifluoro-2-methoxy-2-phenylpropanoic acid.
