Stabilisation of polyethylene and polypropylene glycol through inhibition of a β-positioned hydroxyl group relative to an ether group. A study of modified triethylene and tripropylene glycols

2003 ◽  
Vol 81 (2) ◽  
pp. 273-278 ◽  
Author(s):  
Jens Glastrup
Keyword(s):  
Hydroxyl Group ◽  
Polypropylene Glycol ◽  
Ether Group ◽  
Group A

Tandem transformations of cyclopentene α,α-dichlorocarboxamides into epoxy lactones induced by a γ-hydroxyl group; a short synthesis of the Corey epoxy lactone and its enantiomer

2015 ◽  
Vol 56 (49) ◽  
pp. 6904-6907 ◽  
Author(s):  
Zuleykha R. Valiullina ◽  
Vera A. Akhmetyanova ◽  
Nadezhda A. Ivanova ◽  
Mansur S. Miftakhov
Keyword(s):  
Hydroxyl Group ◽  
Group A ◽  
Short Synthesis

The constituents of Cryptocarya pleurosperma White & Francis. I. Pleurospermine: A new alkaloid of the leaves

1959 ◽  
Vol 12 (1) ◽  
pp. 90 ◽  
Author(s):  
E Gellert
Keyword(s):  
Nitrogen Atom ◽  
Oxygen Atom ◽  
Hydroxyl Group ◽  
Veratric Acid ◽  
The Third ◽  
Tertiary Nitrogen Atom ◽  
Group A ◽  
Francis I ◽  
Alcoholic Hydroxyl ◽  
Tertiary Nitrogen

A new alkaloid pleurospermine, C14Hl9O3N, has been isolated from the leaves of Cryptocarya pleurosperma. Pleurospermine contains a methoxyl group, a phenolic hydroxyl group, and a tertiary nitrogen atom. The third oxygen atom is possibly present as an alcoholic hydroxyl group. On heating with palladium-charcoal the alkaloid yields 4-hydroxy-3-methoxyacetophenone (I), while methylation followed by oxidation gives veratric acid.

Zur Chemie des Phorbols, VIII

1968 ◽  
Vol 23 (12) ◽  
pp. 1584-1597 ◽  
Author(s):  
Michael Gschwendt ◽  
Erich Hecker
Keyword(s):  
Allyl Alcohol ◽  
Lead Tetraacetate ◽  
Hydroxyl Group ◽  
Structural Elements ◽  
Complete Structure ◽  
Relative Configuration ◽  
Alcohol Group ◽  
Partial Structures ◽  
Group A ◽  
Tertiary Hydroxyl

Oxidation of phorbol with one mole of lead tetraacetate yields bisdehydrophorbol, tiglophorbol and small amounts of phorbolacton-semiacetal. By chemical and spectroscopic investigations of bisdehydrophorbol and its derivatives its complete structure 16 is derived based upon the partial structures and structural elements of phorbol (1 - 3) which have been deduced in preceding communications. By consideration of the mechanism of the oxidative scission of the cyclopropanol unit in phorbol the structure 15 of this new tetracyclic diterpene is obtained. 15 has a pentamethyl-tetradecahydro-1H-cyclopropabenzazulene skeleton (tiglian) carrying as functional groups a tertiary hydroxyl group, an α,β-unsaturated tertiary 1.2-ketol group, a primary allyl alcohol group and a α- [hydroxycyclopropyl] -carbinol group. Phorbol is 4.9.12β.13.20-pentahydroxy-tigliadien- (1.6) -on- (3) (15) , bisdehydrophorbol 4.9.12β.20-tetrahydroxy-13.15-seco-tigliatrien- (1.6.15) -dion- (3.13) (16) the conformations of which have been determined. The structure of phorbolacton-semiacetal is determined in the following communication of this series. Based upon the structure of phorbol and additional chemical and spectroscopic evidence the structure of tiglophorbol (17) is also derived. With the data provided the relative configuration and the conformation of six out of the eight asymmetric centers of phorbol is determined.

LYCOPODIUM ALKALOIDS: XVI. ANNOTINE

1964 ◽  
Vol 42 (11) ◽  
pp. 2584-2594 ◽  
Author(s):  
W. A. Szarek ◽  
K. A. H. Adams ◽  
M. Curcumelli-Rodostamo ◽  
D. B. MacLean
Keyword(s):  
Double Bond ◽  
Nitrogen Atom ◽  
Hydroxyl Group ◽  
Tertiary Nitrogen Atom ◽  
Chemical Studies ◽  
Group A ◽  
Instrumental Methods ◽  
Tertiary Hydroxyl ◽  
Plausible Structure ◽  
Tertiary Nitrogen

Annotine, C16H21O3N, is shown to be pentacyclic and to contain a tertiary hydroxyl group, a lactone function, a tertiary nitrogen atom, and a dialkylated double bond. The position of the double bond and the tertiary hydroxyl group relative to the nitrogen atom has been established by Emde degradation of annotine methiodide. The presence of a lactone function is inferred from the reduction of annotine to dihydroannotinol, a hemiacetal, which reacts with 1 mole of ethyl mercaptan. The reduction of the lactone to a diol in an annotine derivative has been carried out. The chemical studies and the examination of annotine and its derivatives by modern instrumental methods allow the assignment of a plausible structure to the alkaloid.

Stereocontrol of Michael hydride reduction by a remote hydroxyl group. A strategy for stereorational total synthesis of spatane diterpenes

1984 ◽  
Vol 106 (7) ◽  
pp. 2211-2213 ◽  
Author(s):  
Robert G. Salomon ◽  
Navzer D. Sachinvala ◽  
Swadesh R. Raychaudhuri ◽  
Donald B. Miller
Keyword(s):  
Total Synthesis ◽  
Hydroxyl Group ◽  
Hydride Reduction ◽  
Group A

Carnaubadiol, a triterpene from carnauba wax

1965 ◽  
Vol 18 (9) ◽  
pp. 1411 ◽  
Author(s):  
CS Barnes ◽  
MN Galbraith ◽  
E Ritchie ◽  
WC Taylor
Keyword(s):  
Hydroxyl Group ◽  
Side Chain ◽  
Spectroscopic Methods ◽  
Carnauba Wax ◽  
Group A ◽  
Tertiary Hydroxyl

By chemical and spectroscopic methods, carnaubadiol, C31H54O2, a constituent of carnauba wax, was shown to contain one secondary and one tertiary hydroxyl group, and one isopropenyl group. A series of degradative reactions yielded a heptanorketone, identical with the known 3β-acetoxyhexanordammaran-20-one, previously obtained from dammarenediol. The structure and configuration of the side-chain were established by oxidation of dihydrocarnaubadiol to the known (-)-(S)-5,6-dimethylheptan-2-one. Carnaubadiol was thus shown to be 24β-methyl- dammar-25-ene-3β,20ξ-diol.

Interactions in aqueous nonelectrolyte systems. Gibbs energy of interaction of the ether group with the hydroxyl group and the amide group

1985 ◽  
Vol 14 (11) ◽  
pp. 781-794 ◽  
Author(s):  
Sushil K. Suri ◽  
Jan J. Spitzer ◽  
Robert H. Wood ◽  
Edwin G. Abel ◽  
Peter T. Thompson
Keyword(s):  
Gibbs Energy ◽  
Amide Group ◽  
Hydroxyl Group ◽  
Ether Group ◽  
Energy Of Interaction

scholarly journals C-Lactam Derivatives of Oleanolic Acid. The Synthesis of C-lactam by Beckmann Rearrangement of C-oxime

2011 ◽  
Vol 6 (12) ◽  
pp. 1934578X1100601
Author(s):  
Barbara Bednarczyk – Cwynar
Keyword(s):  
Double Bond ◽  
Nitrogen Atom ◽  
Oleanolic Acid ◽  
Structure Elucidation ◽  
Beckmann Rearrangement ◽  
Hydroxyl Group ◽  
Chemical Transformations ◽  
Group A ◽  
Derivatives Of ◽  
Carbonyl Function

Oleanolic acid, one of the most known triterpenes, was subjected to different chemical transformations within C-3 β-hydroxyl group, a double bond between C-12 and C-13, and a carboxyl function at C-17 in order to obtain new derivatives. The key compound consists of four six-membered rings (A, B, D, E) and one enlarged ring (C ring) containing a nitrogen atom and a carbonyl function – lactam. This type of derivative can be obtained by Beckmann rearrangement of the appropriate oxime. The lactam can be transformed into thiolactam with the use of Lavesson's reagent. The method is also presented for new derivatives synthesis, as well as their structure elucidation by spectroscopic means.

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