NMR spectra in the spiral mesophase consisting of the nematic material and the optically active compound

1976 ◽  
Vol 21 (2) ◽  
pp. 211-219 ◽  
Author(s):  
Norimasa Kamezawa
Keyword(s):  
Active Compound ◽  
Nmr Spectra ◽  
Optically Active

Lanoconazole and Its Related Optically Active Compound NND-502: Novel Antifungal Imidazoles with a Ketene Dithioacetal Structure

2003 ◽  
Vol 2 (2) ◽  
pp. 147-160 ◽  
Author(s):  
Yoshimi Niwano ◽  
Tetsuto Ohmi ◽  
Akira Seo ◽  
Hiroki Kodama ◽  
Hiroyasu Koga ◽  
...  
Keyword(s):  
Active Compound ◽  
Optically Active ◽  
Ketene Dithioacetal

Controlled release of an optically active compound by hydrogels of acrylic acid and its online detection

2017 ◽  
Vol 96 (5) ◽  
pp. 1221-1227 ◽  
Author(s):  
Leandro G. Aguiar ◽  
Daniel C. Iwakura ◽  
Ana T. S. Semeano ◽  
Rosamaria W. C. Li ◽  
Esmar F. Souza ◽  
...  
Keyword(s):  
Controlled Release ◽  
Acrylic Acid ◽  
Active Compound ◽  
Optically Active ◽  
Online Detection

Studies of the optically active compounds of Anacardiaceae exudates. II. The action of Alkali on the long-chain alicyclic Keto Alcohol of Tigaso Oil

1958 ◽  
Vol 11 (1) ◽  
pp. 64 ◽  
Author(s):  
LK Dalton ◽  
JA Lamberton
Keyword(s):  
Optical Activity ◽  
Active Compound ◽  
Optical Rotation ◽  
Large Change ◽  
Optically Active ◽  
Bicyclic Compound ◽  
Compound I ◽  
Alcoholic Alkali ◽  
Rapid Reaction ◽  
Long Chain

In cold alcoholic alkali the optically active compound I from Tigaso oil undergoes a rapid reaction which involves loss of its conjugated carbonyl system, and a large change, with inversion, of its optical rotation. The reaction is interpreted as a cyclization and the product is provisionally formulated as a bicyclononane derivative IIa. In hot alcoholic alkali, IIa is not the final product ; the bicyclic compound undergoes further reaction to give a mixture in which the unsaturated monocyclic triketone VII (R=C16H31) appears to predominate, but which probably consists of a mixture of VII and VIII (R=C16H31). These can be hydrogenated to a mixture of saturated monocyclic triketones VII and VIII (R =C16H33). The same hydrogenated triketones are obtained if IIa is first hydrogenated and then heated with alcoholic alkali. These triketones are optically active and by oxidation with hypobromite, or with permanganate and then hypobromite, yield bromoform and the chemically homogeneous tribasic acid IX, which still retains optical activity. The isolation of the saturated hydroxydiketone IIb in 4 per cent, yield from hydrogenated Tigaso oil suggests that 11% is present to that extent in the original oil.

Sol–gel thin film deposition and characterization of a new optically active compound: Er2Ti2O7

2001 ◽  
Vol 16 (4) ◽  
pp. 463-473 ◽  
Author(s):  
M. Langlet ◽  
C. Coutier ◽  
J. Fick ◽  
M. Audier ◽  
W. Meffre ◽  
...  
Keyword(s):  
Thin Film ◽  
Active Compound ◽  
Sol Gel ◽  
Thin Film Deposition ◽  
Optically Active ◽  
Film Deposition

Synthesis of Optically Active N6-Alkyl Derivatives of (R)-3-(Adenin-9-yl)-2-hydroxypropanoic Acid and Related Compounds

2003 ◽  
Vol 68 (5) ◽  
pp. 931-950 ◽  
Author(s):  
Marcela Krečmerová ◽  
Miloš Buděšínský ◽  
Milena Masojídková ◽  
Antonín Holý
Keyword(s):  
Nmr Spectra ◽  
Enantiomeric Purity ◽  
Optically Active ◽  
Secondary Amines ◽  
H Nmr ◽  
Alkyl Derivatives ◽  
Optically Pure ◽  
Derivatives Of ◽  
Related Compounds

Reaction of ethyl (R)-oxiranecarboxylate (2a) with various nucleobases (adenine, 6-chloropurine, thymine, cytosine, N6-benzoyladenine, 4-methoxy-5-methylpyrimidin-2(1H)-one and 4-methoxypyrimidin-2(1H)-one) afforded ethyl 3-substituted-2-hydroxypropanoates 4-10. Enantioselectivity of this reaction is dependent on the type of the base: 6-chloropurine, N6-benzoyladenine, 4-methoxy-5-methylpyrimidin-2(1H)-one, thymine and cytosine gave optically pure R enantiomers. In other cases, partial or complete racemization occurred. Optically pure ethyl (R)-3-(6-chloropurin-9-yl)-2-hydroxypropanoate (5a) was hydrolyzed to give (R)-3-(6-chloropurin-9-yl)-2-hydroxypropanoic acid (11). Reactions of 11 with various primary or secondary amines led to N6-substituted (R)-3-(adenin-9-yl)-2-hydroxypropanoic acids 14-19. Enantiomeric purity was determined from 1H NMR spectra measured in the presence of (-)-(R)-1-(9-anthryl)-2,2,2-trifluoroethan-1-ol.

Crystalline inclusion complexes as media of molecular recognitions and selective reactions

2001 ◽  
Vol 73 (7) ◽  
pp. 1137-1145 ◽  
Author(s):  
Fumio Toda
Keyword(s):  
Inclusion Complexes ◽  
Chemical Reaction ◽  
Active Compound ◽  
Inclusion Complexation ◽  
Photochemical Reactions ◽  
Optically Active ◽  
Crystalline Inclusion ◽  
Guest Molecules ◽  
Water Suspension ◽  
Enantioselective Reactions

Hexaol host compounds which include guest molecules maximum in 1:6 ratio were prepared. Aromatic hexaol host, hexahydroxytriphenylene, was found to form chiral inclusion crystal by complexation with achiral guest molecules. Some interesting and important optical resolutions of rac-guests by inclusion complexation with a chiral host were described. When chemical reaction and the inclusion complexation procedures in a water suspension medium are combined, new economical and ecological method of the preparation of optically active compound can be established. When photochemical reactions are carried out in an inclusion crystal with a chiral host, enantioselective reactions occur, and optically active product can be obtained. Several successful reactions are described.

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