Cupressene and Other Diterpenes of Cupressus Species

1979 ◽  
Vol 32 (5) ◽  
pp. 1131 ◽  
Author(s):  
RM Carman ◽  
MD Sutherland
Keyword(s):  
Hydrocarbon Composition ◽  
Diterpene Hydrocarbon ◽  
Optical Rotations

Cupressene, as originally isolated from Cupressus macrocarpa, is shown to be a 1 : 2 mixture of (+) isophyllocladene with (+)-isohibaene (13α-beyer-15-ene) rather than with (-)-hibaene (beyer-15-ene) as previously claimed. Corrections to the optical rotations of (+)-phyllocladinol and (-)-abieta-7,13-diene and g.l.c. data for diterpene hydrocarbons are reported. Analysis of the diterpene hydrocarbon composition of the foliage of 27 specimens from four Cupressus species reveals significantregularities.

Static and Dynamic Studies of Gasoline in View of its Octane Number and its Toxic Effect

2013 ◽  
Vol 12 (7) ◽  
pp. 451-459
Author(s):  
Ashraf Yehia El-Naggar ◽  
Mohamed A. Ebiad
Keyword(s):  
Toxic Effect ◽  
Aromatic Hydrocarbons ◽  
Octane Number ◽  
Liquid Fuel ◽  
Positive Impact ◽  
Hydrocarbon Composition ◽  
Different Temperatures ◽  
Different Seasons ◽  
The One ◽  
The Impact

Gasoline come primarily from petroleum cuts, it is the preferred liquid fuel in our lives. Two gasoline samples of octane numbers 91 and 95 from Saudi Arabia petrol stations were studied. This study was achieved at three different temperatures 20oC, 30oC and 50oC representing the change in temperatures of the different seasons of the year. Both the evaporated gases of light aromatic hydrocarbons (BTEX) of gasoline samples inside the tank were subjected to analyze qualitatively and quantitatively via capillary gas chromatography. The detailed hydrocarbon composition and the octane number of the studied gasoline samples were determined using detailed hydrocarbon analyzer. The idea of research is indicating the impact of light aromatic compounds in gasoline on the toxic effect of human and environment on the one hand, and on octane number of gasoline on the other hand. Although the value of octane number will be reduced but this will have a positive impact on the environment as a way to produce clean fuel.

scholarly journals Lipase Catalyzed Synthesis of Enantiopure Precursors and Derivatives for β-Blockers Practolol, Pindolol and Carteolol

Catalysts ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 503
Author(s):  
Morten Gundersen ◽  
Guro Austli ◽  
Sigrid Løvland ◽  
Mari Hansen ◽  
Mari Rødseth ◽  
...  
Keyword(s):  
Building Block ◽  
Kinetic Resolution ◽  
Enantiomeric Excess ◽  
Catalytic Amount ◽  
Building Blocks ◽  
Β Blocker ◽  
Β Blockers ◽  
Optical Rotations ◽  
Reported Data ◽  
By Products

Sustainable methods for producing enantiopure drugs have been developed. Chlorohydrins as building blocks for several β-blockers have been synthesized in high enantiomeric purity by chemo-enzymatic methods. The yield of the chlorohydrins increased by the use of catalytic amount of base. The reason for this was found to be the reduced formation of the dimeric by-products compared to the use of higher concentration of the base. An overall reduction of reagents and reaction time was also obtained compared to our previously reported data of similar compounds. The enantiomers of the chlorohydrin building blocks were obtained by kinetic resolution of the racemate in transesterification reactions catalyzed by Candida antarctica Lipase B (CALB). Optical rotations confirmed the absolute configuration of the enantiopure drugs. The β-blocker (S)-practolol ((S)-N-(4-(2-hydroxy-3-(isopropylamino)propoxy)phenyl)acetamide) was synthesized with 96% enantiomeric excess (ee) from the chlorohydrin (R)-N-(4-(3-chloro-2 hydroxypropoxy)phenyl)acetamide, which was produced in 97% ee and with 27% yield. Racemic building block 1-((1H-indol-4-yl)oxy)-3-chloropropan-2-ol for the β-blocker pindolol was produced in 53% yield and (R)-1-((1H-indol-4-yl)oxy)-3-chloropropan-2-ol was produced in 92% ee. The chlorohydrin 7-(3-chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one, a building block for a derivative of carteolol was produced in 77% yield. (R)-7-(3-Chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one was obtained in 96% ee. The S-enantiomer of this carteolol derivative was produced in 97% ee in 87% yield. Racemic building block 5-(3-chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one, building block for the drug carteolol, was also produced in 53% yield, with 96% ee of the R-chlorohydrin (R)-5-(3-chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one. (S)-Carteolol was produced in 96% ee with low yield, which easily can be improved.

Hydrocarbon composition of naphtha cuts from Davydovsk and Vishansk crude oils

1974 ◽  
Vol 10 (3) ◽  
pp. 179-182
Author(s):  
Yu. G. Egiazarov ◽  
V. I. Kulikov ◽  
V. V. Kuzyaeva ◽  
A. M. Smol'skii ◽  
T. I. Kozlova ◽  
...  
Keyword(s):  
Hydrocarbon Composition ◽  
Crude Oils

scholarly journals Cuticular hydrocarbons discriminate cryptic Macrolophus species (Hemiptera: Miridae)

2012 ◽  
Vol 102 (6) ◽  
pp. 624-631 ◽  
Author(s):  
C. Gemeno ◽  
N. Laserna ◽  
M. Riba ◽  
J. Valls ◽  
C. Castañé ◽  
...  
Keyword(s):  
Biological Control ◽  
Cuticular Hydrocarbons ◽  
Cross Validation ◽  
Molecular Genetic ◽  
Cuticular Hydrocarbon ◽  
Hydrocarbon Composition ◽  
Dark Spot ◽  
Prediction Errors ◽  
Control Activity ◽  
Genetic Studies

AbstractMacrolophus pygmaeus is commercially employed in the biological control of greenhouse and field vegetable pests. It is morphologically undistinguishable from the cryptic species M. melanotoma, and this interferes with the evaluation of the biological control activity of M. pygmaeus. We analysed the potential of cuticular hydrocarbon composition as a method to discriminate the two Macrolophus species. A third species, M. costalis, which is different from the other two species by having a dark spot at the tip of the scutellum, served as a control. Sex, diet and species, all had significant effects in the cuticular hydrocarbon profiles, but the variability associated to sex or diet was smaller than among species. Discriminant quadratic analysis of cuticular hydrocarbons confirmed the results of previous molecular genetic studies and showed, using cross-validation methods, that M. pygmaeus can be discriminated from M. costalis and M. melanotoma with prediction errors of 6.75% and 0%, respectively. Therefore, cuticular hydrocarbons can be used to separate M. pygmaeus from M. melanotoma reliably.

Response of diesel fuels to pour-depressant additive V�S-238 in relation to fuel hydrocarbon composition

1978 ◽  
Vol 14 (11) ◽  
pp. 804-808 ◽  
Author(s):  
T. N. Veretennikova ◽  
B. A. �nglin ◽  
V. G. Nikolaeva ◽  
T. N. Mitusova ◽  
E. I. Elenskaya
Keyword(s):  
Hydrocarbon Composition ◽  
Diesel Fuels ◽  
Depressant Additive
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