Zur Chemie des Phorbols, VII

Cleavage of phorbol-3-ol-12,13,20-triacetate with sodium-periodate proves the presence of an α,β- unsaturated tertiary 1,2-ketol group in phorbol and its location in the five-membered ring. Accordingly 4-O-methyl-phorbol-3-ol-12,13,20-triacetate is not cleaved by sodium periodate, and by zinc/acetic acid phorbol-12,13,20-triacetate is converted to a 4-deoxy-compound.

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SOME OXIDATION REACTIONS OF DELCOSINE

Canadian Journal of Chemistry ◽

10.1139/v57-058 ◽

1957 ◽

Vol 35 (4) ◽

pp. 397-408 ◽

Cited By ~ 30

Author(s):

Ragini Anet ◽

D. W. Clayton ◽

Léo Marion

Keyword(s):

Acetic Acid ◽

Silver Oxide ◽

Chromic Acid ◽

Mercuric Acetate ◽

Membered Ring ◽

Oxidation Reactions ◽

Ethyl Group ◽

Compound C ◽

Ring Oxidation ◽

Group B

The alkaloid delcosine was oxidized by chromic acid in acetic acid, and also by the Oppenauer reaction, to dehydrodelcosine in which the carbonyl was shown by infrared absorption to be in a pentatomic ring. Oxidation of the alkaloid with silver oxide gave two products: (a) N-desethyldelcosine, which could be N-acetylated or converted back to the original base by ethylation, thus proving the presence of an N-ethyl group; (b) a compound, C24H37O7N, the properties of which agreed best with those of an internal ether, i.e., anhydrohydroxydelcosine. The action of N-bromosuccinimide on the alkaloid produced the same two compounds as silver oxide, plus a derivative, C22H33O7N, that proved to be N-desethyl-anhydrohydroxydelcosine. Potassium permanganate oxidized delcosine to a product, C22H31O7N, that had lost the N-ethyl group, contained the internal ether, and also a carbonyl in a five-membered ring. This same product was obtained on similar oxidation of N-desethyl-anhydrohydroxydelcosine. Oxidation of delcosine with mercuric acetate gave N-desethyldelcosine and N-desethyl-anhydrohydroxydelcosine, together with a compound that was very soluble in water and proved to be the carbinolamine formed by hydroxylation of the methylene in the N-ethyl group. These results are discussed in terms of a structure that is tentatively advanced for delcosine.

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Seven-membered Ring Compounds. V.1The Synthesis of 2,3,4-Trimethoxybenzosuberone-6-acetic Acid and Related Compounds

Journal of the American Chemical Society ◽

10.1021/ja01116a028 ◽

1953 ◽

Vol 75 (20) ◽

pp. 4976-4979 ◽

Cited By ~ 7

Author(s):

Pete D. Gardner ◽

W. J. Horton

Keyword(s):

Acetic Acid ◽

Membered Ring ◽

Ring Compounds ◽

Related Compounds

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Studies in the Cycloproparene Series: Reactions of Alkylidenecycloproparenes With Electrophiles

Australian Journal of Chemistry ◽

10.1071/ch9871375 ◽

1987 ◽

Vol 40 (8) ◽

pp. 1375 ◽

Cited By ~ 13

Author(s):

SJ Buckland ◽

B Halton ◽

Q Mei ◽

PJ Stang

Keyword(s):

Acetic Acid ◽

Ring Expansion ◽

Membered Ring ◽

Ring Cleavage ◽

Vinyl Ethers ◽

Subsequent Reaction ◽

Bromine Water ◽

Delicate Balance ◽

Counter Ion ◽

Anhydrous Acetic Acid

The addition of an electrophile to the alkylidenecycloproparenes (2a-d) is dominated by capture at the exocyclic centre with formation of the corresponding cycloproparenyl cation, e.g. (15). Subsequent reaction with the counter ion is usually accompanied by cleavage of the three-membered ring. Thus compounds (2) give the ethanones (4) with aqueous acids whilst anhydrous acetic acid yields the vinyl acetates (5). Silver(1)-catalysed methanolysis of (2) leads to vinyl ethers (6); the alkyne (7) is formed only from (2d) which carries a vinylic proton. Brominations and bromine water additions lead to products of ring expansion (8)-(10) or ring cleavage (11)-(14) depending upon the conditions employed. These latter reactions demonstrate a delicate balance between cycloproparenylcarbinyl cation formation and cleavage of the three-membered ring.

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FORMATION OF CYCLIC O-2′-HYDROXYETHYLIDENE ACETALS FROM POLYALCOHOLS OF 4-O-LINKED POLYSACCHARIDES

Canadian Journal of Chemistry ◽

10.1139/v65-412 ◽

1965 ◽

Vol 43 (11) ◽

pp. 2978-2984 ◽

Cited By ~ 23

Author(s):

P. A. J. Gorin ◽

J. F. T. Spencer

Keyword(s):

Acid Hydrolysis ◽

Sodium Periodate ◽

Rhodotorula Glutinis ◽

Membered Ring ◽

The Other ◽

Complete Oxidation ◽

Partial Acid Hydrolysis ◽

Ring Form ◽

Hydrolysis Of ◽

By Products

Partial acid hydrolysis of polyalcohols derived from some 1,4-O-linked polysaccharides gave cyclic O-2′-hydroxyethylidene derivatives as by-products in yields of 6–18%. Polysaccharides containing β-links such as Rhodotorula glutinis mannan and cellulose gave rise to 6-membered ring acetals with lesser amounts of the 5-membered ring form. On the other hand, two α-linked polyalcohols, obtained following partial and complete oxidation of starch with sodium periodate, were converted to 5-membered O-2′-hydroxyethylidene acetals.

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Chemistry of meso-Dimethylaminopropenyl- porphyrins and -bisporphyrins: the Synthesis of Australochlorin, a Benzochlorin Isomer.

Australian Journal of Chemistry ◽

10.1071/c96191 ◽

1997 ◽

Vol 50 (5) ◽

pp. 487 ◽

Cited By ~ 5

Author(s):

Dmitry V. Yashunsky ◽

Gelii V. Ponomarev ◽

A. S. Moskovkin ◽

Dennis P. Arnold

Keyword(s):

Acetic Acid ◽

Double Bond ◽

Trifluoroacetic Acid ◽

Membered Ring ◽

Macrocyclic Complexes ◽

Exocyclic Double Bond ◽

Derivatives Of

The nickel(II) complex of meso-dimethylaminoprop-1-enyloctaethylporphyrin (2c) was converted by quaternization and thermolysis into a pair of novel isomeric macrocyclic complexes (3) and (4). These have a fused six-membered ring, and an exocyclic double bond on the neighbouring β-position, and have been named ‘australochlorins’. Heating these compounds in acetic acid leads to the known nickel(II) octaethylbenzochlorin (1) and a novel β-(1-acetoxyethyl)benzochlorin (5). Trifluoroacetic acid promotes the regioselective formation of benzochlorin/porphyrin species from the mononickel(II) complexes of the acrolein derivatives of bis(octaethylporphyrinyl)ethane and trans-ethene.

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Reaction of amines with the bisulphite addition compound of 5-Amino-5-deoxy-D-xylose: Conversion to piperidine derivatives

Australian Journal of Chemistry ◽

10.1071/ch9660675 ◽

1966 ◽

Vol 19 (4) ◽

pp. 675 ◽

Cited By ~ 3

Author(s):

DL Ingles

Keyword(s):

Formic Acid ◽

Sulphur Dioxide ◽

Sodium Periodate ◽

Membered Ring ◽

Compound Viii ◽

Barium Salt ◽

Addition Compound ◽

Piperidine Derivative ◽

Enzymic Browning ◽

Pyridine Salt

The bisulphite addition compound (1) of 5-amino-5-deoxy-D-xylose reacted with cyclohexylamine to form the acyclic derivative (11). With ammonia, benzylamine, morpholine, and piperidine, corresponding salts (IV) of the piperidine derivative D-ido(gluco)-3,4,5-trihydroxy-2-sulphopiperidine (VIII), were isolated. Removal of the amine yielded the crystalline bisulphite addition compound (VIII). Acetylation in the presence of pyridine of the different amine salts (11, IV) and of (VIII) gave an identical acetate (VII), l-acetyl-D-ido(gluco)-3,4,5-triacetoxy-2-sulphopiperidine, isolated as the pyridine salt. Deacetylation of (VII) with barium methoxide gave the barium salt (IX). Oxidation of (IX) with sodium periodate liberated one mole of formic acid, confirming the presence of a six-membered ring containing nitrogen. The significance of these results in the inhibition of non-enzymic browning by sulphur dioxide is discussed.

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The chemistry of food flavour. I. Volatile constituents of passionfruit, Passiflora edulis

Australian Journal of Chemistry ◽

10.1071/ch9721921 ◽

1972 ◽

Vol 25 (9) ◽

pp. 1921 ◽

Cited By ~ 50

Author(s):

KE Murray ◽

J Shipton ◽

FB Whitfield

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Acetic Acid ◽

Benzyl Alcohol ◽

Carbon Number ◽

Membered Ring ◽

Gas Chromatography Mass Spectrometry ◽

Passiflora Edulis ◽

Volatile Constituents ◽

Citronellyl Acetate

The volatile constituents of the purple-skinned passionfruit (Passifora edulis Sims) have been investigated. The volatiles were concentrated, fractionated by gas chromatography and chromatography on silica gel, and the resulting fractions examined by combined gas chromatography-mass spectrometry. The majority of the components identified are esters derived largely from combinations of the alkan-1-ols (C1,2,4,6,8) the alkan-2-ols (C5,7),(Z)-and (E)-hex-3-en-1-ol,(2)-hex-4-en-1-ol,and benzyl alcohol, with acids of even carbon number (acetic, butanoic, hexanoic, octanoic, hex-3-enoic, oct-3-enoic, and 3-hydroxyhexanoic). The non-ester constituents include many of the above free alcohols, acetaldehyde, alkan-2-ones (C3,5,7,9,11), monoterpenes ((E)-β-ocimene, 1,8-cineole, linalool, α-terpineol, citronellol, geraniol, citronellyl acetate, (Z) and(E) five-membered ring linalool oxides), and 1,1,6-trimethyl- l,2-dihydronaphthalene, β-ionone, γ-hexanolac-tone, γ-octanolactone, and the lactone of 2-hydroxy-2,6,6-trimethylcyclohexylidene- acetic acid. Preliminary odour assessment of the constituents has indicated that volatile passionfruit flavour is complex. Many components, especially certain esters, are clearly important and one component, not yet completely characterized, may have particular significance.

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Ectodesmata as Revealed By Freeze-Etch Preparations of Plant Epidermal Cell Walls

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072782 ◽

1973 ◽

Vol 31 ◽

pp. 468-469

Author(s):

N.C. Lyon ◽

W. C. Mueller

Keyword(s):

Electron Microscopy ◽

Acetic Acid ◽

Nitric Acid ◽

Oxalic Acid ◽

Light Microscopy ◽

Epidermal Cell ◽

Cell Walls ◽

Plant Viruses ◽

Plant Leaves ◽

Thin Sections

Schumacher and Halbsguth first demonstrated ectodesmata as pores or channels in the epidermal cell walls in haustoria of Cuscuta odorata L. by light microscopy in tissues fixed in a sublimate fixative (30% ethyl alcohol, 30 ml:glacial acetic acid, 10 ml: 65% nitric acid, 1 ml: 40% formaldehyde, 5 ml: oxalic acid, 2 g: mecuric chloride to saturation 2-3 g). Other workers have published electron micrographs of structures transversing the outer epidermal cell in thin sections of plant leaves that have been interpreted as ectodesmata. Such structures are evident following treatment with Hg++ or Ag+ salts and are only rarely observed by electron microscopy. If ectodesmata exist without such treatment, and are not artefacts, they would afford natural pathways of entry for applied foliar solutions and plant viruses.

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