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.

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.

Dehydration and Stabilization of a Reactive Tertiary Hydroxyl Group in Solid Oral Dosage Forms of BMS-779788

2016 ◽  
Vol 105 (4) ◽  
pp. 1478-1488 ◽  
Author(s):  
Monica L. Adams ◽  
Vijayata Sharma ◽  
Madhushree Gokhale ◽  
Yande Huang ◽  
Kevin Stefanski ◽  
...  
Keyword(s):  
Dosage Forms ◽  
Oral Dosage ◽  
Hydroxyl Group ◽  
Solid Oral Dosage Forms ◽  
Oral Dosage Forms ◽  
Tertiary Hydroxyl

scholarly journals Trifluoroacetylation of Alcohols During NMR Study of Compounds with Bicyclo[2.2.1]heptane, Oxabicyclo[3.3.0]octane and Bicyclo[3.3.0]octane Skeleton

2021 ◽  
Vol 72 (2) ◽  
pp. 156-177
Author(s):  
Constantin I. Tanase ◽  
Anamaria Hanganu ◽  
Constantin Draghici
Keyword(s):  
Nmr Spectra ◽  
Cyclopropane Ring ◽  
Secondary Alcohol ◽  
Primary Alcohol ◽  
1H And 13C Nmr ◽  
Alcohol Group ◽  
Nmr Study ◽  
Group A ◽  
Graphical Presentation ◽  
Nmr Signals

TFA was added to a solution of a bicyclo[2.2.1]heptane azide-alcohol in CDCl3 to correctly characterize the compound, but during 24 h gave the trifluoro acetylated compound in quantitative yield. NMR spectra of the esterified compound helped us also to correctly attribute the NMR signals to the protons, and also confirmed the identification of the carbon atoms. The study was extended to other 14 compounds containing a primary alcohol group alone or with an ethylene ketal, a δ- or -lactone group, a primary and a secondary group, two primary and an alkene group and two primary and a secondary alcohol groups on scaffolds containing bicyclo[2.2.1]heptane, oxabicyclo[3.3.0]octane, bicyclo [2.2.1]heptane constrained with a cyclopropane ring and bicyclo[3.3.0]octane fragments. The esterification of all compounds was also quantitative in 24 to 72 h; this helped us to correct attribute the NMR signals to the protons and carbon atoms of the un-esterified compounds by comparison with those of the trifluoro acetylated compounds. A graphical presentation of 1H- and 13C-NMR spectra of a few un-esterified and esterified compounds are presented in the paper.

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

scholarly journals Stereoselective synthesis of tricyclic compounds by intramolecular palladium-catalyzed addition of aryl iodides to carbonyl groups

2016 ◽  
Vol 12 ◽  
pp. 1236-1242 ◽  
Author(s):  
Jakub Saadi ◽  
Christoph Bentz ◽  
Kai Redies ◽  
Dieter Lentz ◽  
Reinhold Zimmer ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Stereoselective Synthesis ◽  
Carbonyl Groups ◽  
Relative Configuration ◽  
X Ray ◽  
Cyclization Process ◽  
Tricyclic Compounds ◽  
Methoxycarbonyl Group ◽  
Palladium Catalyzed ◽  
Group A

Starting from γ-ketoesters with an o-iodobenzyl group we studied a palladium-catalyzed cyclization process that stereoselectively led to bi- and tricyclic compounds in moderate to excellent yields. Four X-ray crystal structure analyses unequivocally defined the structure of crucial cyclization products. The relative configuration of the precursor compounds is essentially transferred to that of the products and the formed hydroxy group in the newly generated cyclohexane ring is consistently in trans-arrangement with respect to the methoxycarbonyl group. A transition-state model is proposed to explain the observed stereochemical outcome. This palladium-catalyzed Barbier-type reaction requires a reduction of palladium(II) back to palladium(0) which is apparently achieved by the present triethylamine.

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.

THE EFFECTS OF ALCOHOL INTAKE AND INDUCED FRUSTRATION ON THE DISPOSITION TO START FIRES

2001 ◽  
Vol 29 (6) ◽  
pp. 547-556 ◽  
Author(s):  
Renée Perrin-Wallqvist ◽  
Lena Eriksson ◽  
Torsten Norlander
Keyword(s):  
Placebo Group ◽  
University Students ◽  
Short Story ◽  
Alcohol Intake ◽  
Control Group ◽  
Alcohol Group ◽  
Projective Test ◽  
Group A

The object of the present study was to see whether there are tendencies towards reactive arson, measured as a relation between frustration, intoxication and a disposition to start fires. One hundred individuals, 50 men and 50 women, participated. All were students and they were randomly assigned to each of five experimental groups, namely a Control Group, a Placebo Group, a Frustration Group, an Alcohol Group and an Alcohol + Frustration Group. A projective test was devised which required the participant to complete a short story where the content involved a person who had suffered humiliation and persecution and who was fingering a box of matches in his/her pocket. Results indicated that frustration increases the probability of starting fires, but, in this study, alcohol did not increase the degree of relation to fire. Results also suggest that there are strong cognitive barriers in a population of university students against fantasizing about starting fires.

scholarly journals Crystal structure of (20S)-21-[4-(2-hydroxypropan-2-yl)-1H-1,2,3-triazol-4-yl]-20-(4-methylpentyl)-5-pregnen-3β-ol with an unknown solvate

2018 ◽  
Vol 74 (4) ◽  
pp. 465-468
Author(s):  
Hugo Santalla ◽  
Saray Argibay
Keyword(s):  
Crystal Structure ◽  
Solvent Molecule ◽  
Hydroxyl Group ◽  
Crystal Data ◽  
Chemical Formula ◽  
Isopropyl Group ◽  
Terminal Position ◽  
Acta Cryst ◽  
The Given ◽  
Tertiary Hydroxyl

In the title cholesterol analogue, [systematic name: (3S,8S,9S,10R,13S,14S,17R)-17-{(S)-1-[4-(2-hydroxypropan-2-yl)-1H-1,2,3-triazol-1-yl]-6-methylheptan-2-yl}-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-3-ol] C32H53N3O2, a new chain, including an intermediate triazole and a tertiary hydroxyl group in the terminal position, has been added at position 20 inducing a change in its stereochemistry. In the crystal, molecules are linked by O—H...O and O—H...N hydrogen bonds, forming layers lying parallel to (-201) and enclosing R 4 4(36) ring motifs. The isopropyl group is disordered about two positions with a refined occupancy ratio of 0.763 (5):0.237 (5). A region of disordered electron density was corrected for using the SQUEEZE routine in PLATON (Spek (2015). Acta Cryst. C71, 9–18). The given chemical formula and other crystal data do not take into account the unknown solvent molecule(s).

Sign in / Sign up

Export Citation Format

Share Document