Multifloramine

Further details concerning the H NMR spectra of kreysigine, floramultine, and multifloramine (1) have been published. (98) The high frequency absorption of the AT-methyl protons (<5 3-0) in [135], isolated... 

Nonphenolic isoquinolines 99a,b were subjected to oxidation with TTFA (54) and with RUTFA (55) to give the homoaporphines 100a,b. Moreover, oxidation of 99c with TTFA in trifluoroacetic acid gave 100c, while 99d provided 101 under the same conditions. Treatment of 101 with sulfuric acid resulted in smooth dienone-phenol rearrangement with concomitant debenzylation to give an 81% yield of ( )-multifloramine (83e) (56). 

An improved synthesis of polyhydroxybenzylisoquinolines without protection of the hydroxy-groups has been reported, in which Bischler-Napieralsky ring closure of the appropriate amide is achieved with phosphorus oxychloride in acetonitrile coclaurine, isococlaurine, and reticuline, as well as a key intermediate in the synthesis of multifloramine, have been prepared in this way. 

The oxidation of phenolic phenethylisoquinolines has been studied in some detail. With iron(iii) chloride the bases (68 R = H and R = OMe) have been oxidised to the homoproaporphine bases (69 R = H and OMe), and the base (70) has been oxidised to the homoproaporphine (71), which yielded the homoaporphine alkaloid multifloramine when subjected to dienone-phenol rearrangement. In this last process, when the dienone (71) was treated with concentrated hydrochloric acid in glacial acetic acid, the mixed acetal (72 R = Me), convertible into the hemiacetal (72 R = H), was isolated. ... 

Some years ago, three alkaloids, namely, kreysigine (31a), floramul-tine (32), and multifloramine (33), were isolated from Kreysigia multiflora 6, 20). Recently, a fourth alkaloid, (— )-kreysigine (31b) was isolated from Bvlbocodium vernum (17). The chemical behavior of this alkaloid has not been described. 

The assignment of S-configuration to multifloramine was accomplished by comparison with the synthetic sample 21). 

Total syntheses of multifloramine (94) were achieved as follows. The diphenolic isoquinoline 88 was subjected to phenol oxidation with... 

Moreover, photolysis of 188 in aqueous ethanol in the presence of sodium hydroxide and sodium iodide gave androcymbine (139) (62). On the other hand, when the above photolysis was done without sodium iodide it afforded only multifloramine (94) (62). 

Homoaporphines and Homoproaporphines.—A new homoaporphine from C. cornigerum is CC-24 (219). Photolysis of the appropriate bromotetrahydro-phenethylisoquinolines can lead to racemic multifloramine (218), kreysigine (220), or 0-methylkreysiginone (221). In each of these syntheses the bromine is situated either at C-8 or at C-2 of the tetrahydrophenethylisoquinoline precursor. ... 

Multifloramine, K2 Multiflorenol, T42 Muscarine, Y20 Muscone, A32 Mustakone, T18 Muurolenes, T18 Mycobactin, Y22 Mycosamine, Y26 Myricanol, YIS cw-myrtanol, T9 rrfln -myrtanol, T8 Myrtenal, T9 Myrtenol, T9... 

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