Cyclopenta phenanthrenes

Ethyl 1 /T-azepine-l-carboxylate (1) and l,3-diphenyl-2/7-cyclopenta[/]phenanthren-2-one (26) (phencyclone) in refluxing benzene undergo a rapid peri- and regioselective cycloaddition to give the [4 + 2] 7t-e rfn-adduct 28 and not, as was first proposed, a [6 + 2] 7r-adduct.264 Subsequently, however, it was found that at room temperature a [2 + 4] 7r-cw/<>-adduct 27 is formed which readily undergoes a Cope rearrangement to the [4 + 2] endo,anti-adduct 28. 

A review of Diels-Alder reactions of fullerenes with acyclic and cyclic dienes has been presented. The addition of substituted pyrimidine o-quinodimethanes (75) to [60]fullerenes yields novel organofullerenes (76) bearing a pyrimidine nucleus covalently attached to the Ceo cage (Scheme 26). The Diels-Alder dimerization of cyclopenta[/]phenanthrene (77) with isobenzindene (78) yields the dimer (79) in 85% yield (Scheme 27). Further evidence has been supplied to support an early reorganization of the r-network in the dimerization of 2-methoxycarbonylbuta-1,3-diene. The Lewis acid-catalysed Diels-Alder reactions of acrylate derivatives of new carbohydrate-based chiral auxiliaries with cyclohexadiene show excellent endo. exo... 

Emulsions based on lipophilic iodized and/or bromated substances with emulsifiers and derivatives of cyclopenta-phenanthrene Polyiodinated phenyl fatty acid compoimds Emulsion of iodinated lipids 6-Iodoethylated starch... 

Cycloaddition reaction of 2,3-diphenylcyclopropenone with l,3-diphenyl-2//-cyclopenta[/]-phenanthren-2-one in chlorobenzene at 150°C for 80 hours under argon in a sealed tube produced 9,10,12,13-tetraphenyl-ll//-cyclohepta[/]phenanthren-ll-one in 29% yield. 

The steroids constitute a group of structurally related compounds that are widely distributed both in the plant and the animal kingdom. The basic nucleus of these physiologically potent and biochemically dynamic medicinal compounds do possess a more or less similar stereochemical relationship. The steroids, in gemeal, have been found to contain either the partly or completely hydrogenated 17H-cyclopenta-phenanthrene nucleus. 

Common Name 13-methyl-17-ethynyl-l7-hydroxy-1,2,3,4,6,7,8,9,11,12,13,14,16,17-tetra-decahydro-15H-cyclopenta(a)phenanthren-3-one... 

Convenient starting materials are the ethers of 3-hydroxy-13-methyl-1,4,6,7,8,9,11,12,13,-14,16,17-dodecahydro-15H-cyclopenta(a)phenanthren-17-one described in U.S. Patent 2,655,518, according to U.S. Patent 2,691,028 mhere the folloming preparation is also de-scribad. The methyl ether is also designated as 3-methoxy-17-oxo-2,5-estradlene. 

Although 1-vinylnaphthalene thermally reacts with 4-acetoxy-2-cyclopenten-1-one (98) to regioselectively afford 99, the isomer 2-vinylnaphthalene gives the same thermal cycloaddition with low yield (30 %) and reacts satisfactorily only with 98 at 10 kbar (Scheme 5.10). Both products 99 and 101 were converted into the cyclopenta[a]phenanthren-15-one (100) and cyclopenta[c]phenanthren-l-one (102) isomers. Acetoxyketone 98 acts as a synthetic equivalent of cyclo-pentadienone (114 in Scheme 5.14) in cycloaddition reactions [33]. 

Steroids, compounds with a cyclopenta[a]phenanthrene skeleton (15), include a wide range of natural products such as sterols (e.g., cholesterol), sex hormones, adrenocorticoid hormones, cardiac glycosides and vitamin D [31]. Sterols are steroids having a hydroxyl group at position 3 of the basic skeleton. Steroids can be found both in plants and in animals. 

Fig. 14 Structures of cyclopenta[(2]phenanthrene derivatives and their carbocations and carboxonium ions.

Convenient starting materials are the ethers of 3-hydroxy-13-methyl-l,4,6,7,8,9,ll,12,13,14,16,17-dodecahydro-15H-cyclopenta-a-phenanthren-... 

To a refluxing solution of 10 parts of 3-methoxy-17-ethynyl-17-hydroxy-13-methyl-l,4,6,7,8,9,ll,12,13,14,16,17-dodecahydro-15H-cyclopenta-a-phenanthrene in 500 parts of methanol, 20 parts of glacial acetic acid are added. Refluxing is continued for 7 minutes, water is added to the point of turbidity and the reaction mixture is permitted to come to room temperature. The precipitate is collected on a filter and recrystallized from aqueous methanol. The 13-methyl-17-ethynyl-17-hydroxy-l,2,3,4,6,7,8,9,ll,12,13,14,... 

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