Total Synthesis of Indole and Dihydroindole Alkaloids. XV. Further Chemistry of Vindoline

Kutney, James P.; Bunzli-Trepp, U.; Honda, Toshio; Katsube, Junki; Worth, Brian R.

doi:10.1002/hlca.19780610508

Cited by 10 publications

(5 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Mass spectrometric fragmentations of Aspidosperma alkaloids like 4 and 10 are well described (Budzkiewicz et al, 1964;Moza et a / . , 1983;Kutney et a/., 1978;Sariaslani et a/., 1984), and proved useful in characterizing 10. The molecular ion at mlz 498 (M + 1 peak) indicated a structure containing one hydrogen atom less than 4.…”

Section: Resultsmentioning

confidence: 99%

PHOTOCHEMICAL OXIDATION OF VINDOLINE and 16‐O‐ACETYLVINDOLINE

J.Filippelli

Reeg

Sariaslani

et al. 1988

Photochem & Photobiology

View full text Add to dashboard Cite

Photooxidation of 16-0-acetylvindoline in methanol using chlorpromazine.HC1 as a photosensitizing agent produces nearly quantitative yields of an iminium derivative. The 16-0-acetylvindoline-iminium product was characterized spectrally by proton NMR and mass spectrometry; and by chemical reduction with sodium borodeuteride. Proton NMR and mass spectral analyses of the reduced product revealed that deuterium was stereospecifically incorporated into the 3-a-position. The iminium product formed by photochemical oxidation is identical to that produced by copper oxidases and peroxidase. Photochemical oxidation provides direct evidence for the involvement of free radicals in Aspidospermu alkaloid transformations.

show abstract

Section: Resultsmentioning

confidence: 99%

PHOTOCHEMICAL OXIDATION OF VINDOLINE and 16‐O‐ACETYLVINDOLINE

J.Filippelli

Reeg

Sariaslani

et al. 1988

Photochem & Photobiology

View full text Add to dashboard Cite

show abstract

“…A compound with properties similar to the isolated metabolite 5 was reported as a mercuric acetate oxidation product of 14,15-dihydro-16-acetoxyvindoline (9) (7). Attempts to synthesize this compound by published methods were unsuccessful.…”

Section: Resultsmentioning

confidence: 99%

“…Attempts to prepare the metabolite directly by chemical methods were unsuccessful; however, the 16-acetoxy derivative had been reported earlier by Kutney et al. (7). Authentic samples of 3-oxo-l4,15-dihydro-16-acetoxyvindoline (8) and 5-oxo-l4,15-dihydro-16-acetoxyvindoline (7) were obtained (7), and we also prepared these compounds using 14,15-dihydro-16-acetoxyvindoline (9) as starting material for the mercuric acetate oxidation.…”

Section: Resultsmentioning

confidence: 99%

“…The resulting solution was adjusted to pH 10 with 58% ammonium hydroxide solution and filtered. The precipitate was washed with water and dried under vacuum to yield 16-acetoxy-14,15-dihydrovindoline (9) as a white amorphous solid (1.35 g) ( 7): uv X max (EtOH) 211 (log e 4.59), 247 (3.85), 301 (3.75); ir (KBr) 3380, 2940, 1750, 1600, 1450, 1360and 1255; 'H-nmr(CDC13)0.5 1 (3H, t,_/=7 Hz, H-18), 1.98(3H, s, OCOCH,), 2.06(3H, s, OCOCH3), 2.62 (3H, s, NCH3), 3.67 (1H, s, H-2), 3.78 (6H, s, OCH3), 5.90 (1H, s, H-17), 6.05 (1H, d,/=2 Hz, H-12), 6.30 (1H, dxd J=8 and 2 Hz, H-10), 7.0 (1H, d,J=8 (8) and 5-oxo-l 4,15-dihydro-l6-acetoxyvindoline (7).-The 3-oxo-(8) and 5-oxo-(7) derivatives were prepared by mercuric acetate oxidation of 14,15-dihydro-16-acetoxyvindoline (9) by the method of Kutney et al (7). Mercuric acetate (4.3 g) and 9 (1.35 g) were dissolved in dry dioxane (25 ml) and heated under reflux in an atmosphere of nitrogen for 20 h. The mixture was cooled, diluted with methanol (250 ml), and treated with hydrogen sulfide for 45 min followed by nitrogen for 30 min.…”

Section: Experimental General Experimentalmentioning

confidence: 99%

“…The residue was dissolved in chloroform and applied to a column (100 g silica gel, 3*32 cm), which was eluted with chloroform at a flow rate of 2.5 ml/min, while 15 ml fractions were collected. 5-Oxo-14,15-dihydro-16-acetoxyvindoline (7) was eluted ion fractions 133 to 235 (163 mg) (7): uv X max (EtOH) 212 (log e 4.49), 247 (3.79), 300(3.66); 'H-nmr (CDC13), 2.0 (3H, s, OCOCH3), 2.1 (3H, s, OCOCH3), 2.65 (3H, s, NCH3), 3.5 (1H, s, H-21), 3.75 (1H, s, H-2), 3.8 (6H, s, OCH3 andC02CH3), 5.75 (1H, s, H-17), 6.1 (1H, d,_/=8 Hz, H-9); mass spectrum, mle (tel. int.)…”

Section: Experimental General Experimentalmentioning

confidence: 99%

See 2 more Smart Citations

Oxidative Transformations of 14,15-Dihydrovindoline by Streptomyces griseus

Eckenrode¹,

Rosazza²

1983

J. Nat. Prod.

View full text Add to dashboard Cite

Reductions by Metal Alkoxyaluminum Hydrides

Málek

1985

Organic Reactions

View full text Add to dashboard Cite

Since the discovery of the reducing properties of diborane (1939), alkali metal borohydrides (1943), and alkali metal aluminohydrides (1946) by H. I. Schlesinger, H. C. Brown, W. G. Brown, and co‐workers, considerable effort has been expended to enhance the versatility and selectivity of these widely used hydride reagents. Whereas diborane exhibits medium reaction large differences exist between sodium borohydride and lithium aluminum hydride. In contrast to the reducing action of sodium borohydride, limited originally to aldehydes, ketones, and acid chlorides, lithium aluminum hydride readily attacks almost all reducible groups. The first progress in bridging this gap in reactivity can be traced to the availability of reagents that are easily prepared by addition of Lewis acids such as boron and aluminum halides to sodium borohydride and lithium aluminum hydride; in this manner diborane, chloroaluminum hydrides, and aluminum hydride have been made accessible as reducing agents. Parallel development led to sodium alkoxyborohydrides with generally higher reactivity than the parent hydride and to alkoxyaluminum hydrides, with markedly lower reactivity and increased chemoselectivity. On the other hand, the reducing capability of sodium borohydride and lithium aluminum hydride has been enhanced by the use of metal salt–hydride systems. A large number of other complex metal hydrides have gained importance as selective reducing agents: lithium aluminum hydride–nitrogen base complexes, sodium cyanoborohydride, lithium cyanoborohydride, sulfurated sodium borohydride, zinc borohydride, diisobutylaluminum hydride, alkylaluminum compounds such as triisobutylaluminum, and tri‐ n ‐butyltin hydride. Sterically hindered organoboranes such as lithium tri‐ sec ‐butylborohydride (L‐Selectride) exhibit excellent selectivity in reduction reactions. High asymmetric induction can be achieved with some chiral organoboranes. Lithium triethylborohydride (Super‐Hydride) is a selective and exceptionally powerful reducing agent. These complex metal hydrides often provide better regio‐ and stereoselectivities than those achieved with alkoxy‐substituted hydrides; nevertheless, the alkoxyhydrides are readily available and continue to be widely used as reducing agents. The purpose of this chapter is to present a critical review of reductions of the following compounds by metal alkoxyaluminum hydrides, alkoxyaluminum hydrides, and chiral metal alkoxyaluminohydride complexes: hydrocarbons, peroxides, ozonides, halogen compounds, unsaturated alcohols, aromatic alcohols, ethers, 1,2‐oxides, aldehydes, ketones, quinones, acetals, and ketals. The literature is covered through December 1981. Important papers that appeared through September 1982 are also reviewed. Some reactions relating to other than reducing properties of these hydrides are included for completeness. The emphasis is on the scope, limitations, and synthetic utility of the hydrides in reduction reactions and on the optimum conditions for their application as reducing agents. Currently accepted views of reaction mechanisms are discussed. Comparisons with reductions by other complex metal hydrides are limited to the most important transformations of the functional groups.

show abstract

Total Synthesis of Indole and Dihydroindole Alkaloids. XV. Further Chemistry of Vindoline

Cited by 10 publications

References 28 publications

PHOTOCHEMICAL OXIDATION OF VINDOLINE and 16‐O‐ACETYLVINDOLINE

PHOTOCHEMICAL OXIDATION OF VINDOLINE and 16‐O‐ACETYLVINDOLINE

Oxidative Transformations of 14,15-Dihydrovindoline by Streptomyces griseus

Reductions by Metal Alkoxyaluminum Hydrides

Contact Info

Product

Resources

About