Regiospecific Internal Desaturation of Aliphatic Compounds by a Mutant Rhodococcus Strain

1999 ◽  
Vol 65 (12) ◽  
pp. 5636-5638 ◽  
Author(s):  
Kenzo Koike ◽  
Katsutoshi Ara ◽  
Shigehito Adachi ◽  
Hirofumi Takigawa ◽  
Hajime Mori ◽  
...  
Keyword(s):  
Double Bond ◽  
Methyl Groups ◽  
Aliphatic Compounds ◽  
Oxidative Pathway ◽  
Rhodococcus Strain

ABSTRACT A mutant Rhodococcus strain lacking the ability to utilize 1-chlorohexadecane was found to cis-desaturate aliphatic compounds, such as 1-chlorohexadecane,n-hexadecane, and heptadecanonitrile, yielding corresponding products with a double bond mainly at the ninth carbon from the terminal methyl groups. A new oxidative pathway involving thecis-desaturation step was suggested for alkane utilization by Rhodococcus spp.

scholarly journals Crystal structure ofN′′-benzyl-N′′-[3-(benzyldimethylazaniumyl)propyl]-N,N,N′,N′-tetramethylguanidinium bis(tetraphenylborate)

2015 ◽  
Vol 71 (12) ◽  
pp. o1086-o1087
Author(s):  
Ioannis Tiritiris ◽  
Willi Kantlehner
Keyword(s):  
Crystal Structure ◽  
Double Bond ◽  
Positive Charge ◽  
Planar Geometry ◽  
Methyl Groups ◽  
Two Dimensional ◽  
Single Bond ◽  
Double Bond Character ◽  
Bond Lengths ◽  
Bond Character

In the crystal structure of the title salt, C24H38N42+·2C24H20B−, the C—N bond lengths in the central CN3unit of the guanidinium ion are 1.3364 (13), 1.3407 (13) and 1.3539 (13) Å, indicating partial double-bond character. The central C atom is bonded to the three N atoms in a nearly ideal trigonal–planar geometry and the positive charge is delocalized in the CN3plane. The bonds between the N atoms and the terminal methyl groups of the guanidinium moiety and the four C—N bonds to the central N atom of the (benzyldimethylazaniumyl)propyl group have single-bond character. In the crystal, C—H...π interactions between the guanidinium H atoms and the phenyl C atoms of the tetraphenylborate ions are present, leading to the formation of a two-dimensional supramolecular pattern parallel to theacplane.

Extractives of Australian timbers. X. Autoxidation and other reactions of the conjugated side-chain of eberlin lactone. Isolation of a new isomer of ebelin lactone

1970 ◽  
Vol 23 (10) ◽  
pp. 2085 ◽  
Author(s):  
RA Eade ◽  
J Ellis ◽  
JS Shannon ◽  
HV Simes ◽  
JJH Simes
Keyword(s):  
Double Bond ◽  
Solid State ◽  
Osmium Tetroxide ◽  
Side Chain ◽  
Methyl Groups ◽  
Stepwise Manner ◽  
Terminal Double Bond ◽  
Conjugated Triene

The conjugated triene side-chain of ebelin lactone has been degraded in a stepwise manner using osmium tetroxide. A new isomer of ebelin lactone has been isolated from the sapogenin mixture and has been assigned the structure (9) in which the 25(26) double bond has the cis configuration. Autoxidation of ebelin lactone in the solid state yields a mixture from which three compounds have been isolated and identified; all three arise from oxidation of the side-chain at the terminal double bond and methyl groups.

The Cumulative Acceleration by Methyl Substituents on the Rate of Addition of 4-Chlorobenzenesulfenyl Chloride to Olefins

1973 ◽  
Vol 51 (15) ◽  
pp. 2463-2468 ◽  
Author(s):  
George H. Schmid ◽  
Dennis G. Garratt
Keyword(s):  
Double Bond ◽  
Methyl Groups ◽  
Stopped Flow ◽  
Carbon Double Bond ◽  
Kinetically Controlled

The rate of addition of 4-chlorobenzenesulfenyl chloride to ethylene and all six of its methylated derivatives has been measured in 1,1,2,2-tetrachloroethane at 25° by means of the stopped flow and a competitive technique. A plot of log krelvs. the number of methyl groups on the carbon–carbon double bond is linear. This establishes that the methyl groups have a cumulative acceleration on the rate contrary to previous reports. The use of the competitive method of obtaining rates of arenesulfenyl chloride additions to olefins suffers from the fact that thermodynamically rather than kinetically controlled product mixtures are often formed.

scholarly journals N,N,N′,N′,N′′,N′′,N′′′,N′′′-Octamethyl(but-2-yne)bisamidinium bis(tetraphenylborate)

IUCrData ◽  
2016 ◽  
Vol 1 (2) ◽  
Author(s):  
Ioannis Tiritiris ◽  
Ralf Kress ◽  
Willi Kantlehner
Keyword(s):  
Double Bond ◽  
Bond Length ◽  
Triple Bond ◽  
Carbon Chain ◽  
Methyl Groups ◽  
Two Dimensional ◽  
Single Bond ◽  
Asymmetric Unit ◽  
Phenyl Rings ◽  
Bond Character

The asymmetric unit of the title salt, C12H24N42+.2C24H20B−, comprises half a cation and one tetraphenylborate ion. An inversion centre is situated at the mid-point of the triple C[triple-bond]C bond in the cation. The bisamidinium C—N bonds [1.3249 (11) and 1.3267 (11) Å] have double-bond character and both positive charges are delocalized between the dimethylamino groups. The bonds between the N atoms and the terminal C-methyl groups all have values characteristic for a typical single bond [1.4656 (12)–1.4687 (12) Å]. The acetylenic bond length [1.1889 (18) Å] is consistent with a triple C[triple-bond]C bond and the butyne carbon chain is almost linear. C—H...π interactions between the bisamidinium methyl H atoms and the phenyl C atoms of the tetraphenylborate ions are present. The phenyl rings form aromatic pockets, in which the cations are embedded. This leads to the formation of a two-dimensional supramolecular pattern in theabplane.

Site of H Atom Attack on Uracil and Its Derivatives in Aqueous Solution

1985 ◽  
Vol 40 (3-4) ◽  
pp. 292-294 ◽  
Author(s):  
Suresh Das ◽  
David J. Deeble ◽  
Clemens von Sonntag
Keyword(s):  
Aqueous Solution ◽  
Double Bond ◽  
Pulse Radiolysis ◽  
Hydrogen Abstraction ◽  
Methyl Groups ◽  
Oh Radicals ◽  
Hydrogen Atoms ◽  
Sugar Moiety ◽  
Reducing Properties

Hydrogen atoms from the radiolysis of water at pH 1.6 add to the 5,6-double bond of pyrimidines. The preferen­tial site of attack is the C(5) position (values in brackets) in the case of 6-methyluracil (87%), 1,3-dimethyluracil (71%), uracil (69%) and poly(U) (60%). This reaction yields a radical of reducing properties which can be monitored by its reaction with tetranitromethane in a pulse radiolysis experiment. In thymine (37%), thymidine (32%) and 1,3-dimethylthymine (25%) H-addition no longer pre­ferentially occurs at C(5), but addition is now mainly at C(6). Hydrogen abstraction from the methyl groups or the sugar moiety is negligible (≦ 5.5%). A comparison is made with literature values for the equivalent reactions of OH radicals.

THE ASSAY OF SUBCUTANEOUSLY INJECTED ANDROGENS IN THE CASTRATED RAT

1963 ◽  
Vol 42 (2) ◽  
pp. 245-253 ◽  
Author(s):  
Ralph I. Dorfman ◽  
Adeline S. Dorfman
Keyword(s):  
Double Bond ◽  
Levator Ani ◽  
Seminal Vesicles ◽  
Ventral Prostate ◽  
Methyl Groups ◽  
Albino Rat ◽  
Once Daily ◽  
Methyl Group ◽  
Assay Procedure ◽  
Androgenic Activity

ABSTRACT An assay procedure using the immature castrated albino rat is described using the weight of the seminal vesicles, ventral prostate, and levator ani as end-points in a ten day assay. The sensitivity was of the order of 0.6 mg of testosterone injected subcutaneously once daily in an aqueous suspending medium. The precision was adequate as judged by the λ values of 0.096 to 0.137 for the seminal vesicles, 0.128 to 0.162 for the ventral prostate, and 0.171 to 0.248 for the levator ani. Activity of testosterone was increased significantly by esterification, by introduction of the 17α-methyl group, and by reduction of the Δ4 double bond to the 5α form. Androgenic activity was decreased significantly by oxidation of the 17β-hydroxy group to the 17-keto group and introduction of methyl groups at the 2α- or 6α-positions.

Recent investigations on the nature of sterol intermediates in the biosynthesis of cholesterol

1972 ◽  
Vol 180 (1059) ◽  
pp. 125-146 ◽  
Keyword(s):  
Double Bond ◽  
Carbon Atom ◽  
Rat Liver ◽  
Liver Homogenate ◽  
Methyl Groups ◽  
Double Bonds ◽  
Animal Tissues ◽  
Methyl Group ◽  
Chromatographic Methods

Lanosterol(4,4,14α-trimethyl-cholesta-8,24-dien-3β-ol) has been proposed as the primary product of the cyclization of 2,3-epoxysqualene in animal tissues. Enzymic conversion of lanosterol to cholesterol requires reduction of the ∆ 24 double bond, removal of the three extra methyl groups, and shift of the nuclear double bond from ∆ 8 position to the ∆ 5 position. Until very recently, all of the proposed sterol intermediates in the biosynthesis of cholesterol possessed nuclear double bonds in the ∆ 8 , ∆ 7 , ∆ 5,7 or ∆ 5 positions. Consideration of possible mechanisms for the removal of the methyl group at carbon atom 14 of sterol precursors led to our demonstration of the presence of cholest-8(14)-en-3β-ol in animal tissues and establishment of the convertibility of this sterol to cholesterol in rat liver homogenate preparations. Reports (from other laboratories) of the stereospecific loss of the 15α-hydrogen of lanosterol upon enzymic conversion to cholesterol led to the demonstration of the convertibility of cholesta-8,14-dien-3β-ol, cholesta-7,14-dien-3β-ol, 14α-methyl-cholest-7-en-3β,15-diol, cholest-8(14)-en-3β,15α-diol, and cholest-8(14)-en-3β,15β-diol to cholesterol in rat liver preparations. We have recently developed chromatographic methods permitting the resolution of all of the C 27 sterols in question. The results of recent experiments directed towards an understanding of the detailed metabolism of these compounds are presented herein.

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