Zobrazeno 1 - 10
of 64
pro vyhledávání: '"Frans Borremans"'
Ten new crystal structures of cis and trans bicyclic diketopiperazines (DKPs) of thia-pipecolic acid (with sulfur in the β, γ or δ position) or thia-proline (with sulfur in the β or γ position) and N-methyl phenylalanine [(NMe)Phe]: cyclo[(β-S)
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4f76a62a4c2648a5fb1883e1de49f391
https://europepmc.org/articles/PMC5744420/
https://europepmc.org/articles/PMC5744420/
Publikováno v:
Bulletin des Sociétés Chimiques Belges. 80:701-706
It is found that long range phenomena involving H-2 atoms in 1,3-dioxolanes are “atypical”. The sign of 2J(CH2–2) is restated to be positive. Both coupling values, 2J and 4J follow a non-monotonous series in bicyclic 4,5-cyclano-1,3-dioxolanes.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::505de63f0dd6ed0d963171fb9aed9166
https://doi.org/10.1002/bscb.19710800540
https://doi.org/10.1002/bscb.19710800540
Publikováno v:
Bulletin des Sociétés Chimiques Belges. 92:999-1010
The preparation of the racemic title compound is reported. An extensive 1H and 13C nmr study reveals the presence of four rotameric states about the two amide bonds (Table 4) and discloses that all four isomers possess almost identical twist-boat rin
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::b4f2b05d3406100970bccd1687393aef
https://doi.org/10.1002/bscb.19830921109
https://doi.org/10.1002/bscb.19830921109
Autor:
Frans Borremans, Marc J. O. Anteunis
Publikováno v:
Bulletin des Sociétés Chimiques Belges. 85:673-679
The rotameric distribution in the axial and equatorial halomethyl group in the 2-methyl-5-halomethyl substituted 1,3-dioxanes is determined qualitatively and a rationale is proposed. The data indicate an attractive 1,3-synaxial interaction between th
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::d19ea885315bbb948a7332bf6b0b1994
https://doi.org/10.1002/bscb.19760850907
https://doi.org/10.1002/bscb.19760850907
Publikováno v:
Bulletin des Sociétés Chimiques Belges. 99:379-387
The four Z/E isomeric states of the linear pentapeptide Pic(3′-OH)-Thr-D-Abu-Pro-MePhe-OH are characterized by two-dimensional proton NMR methods and some of their conformational features are discussed. The title compound as obtained from Virginiam
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::2e08de6587a55122de9fa9d12d6cef5e
https://doi.org/10.1002/bscb.19900990603
https://doi.org/10.1002/bscb.19900990603
Publikováno v:
Bulletin des Sociétés Chimiques Belges. 94:39-49
Amidoalkylation of suitably substituted benzo[b] furans and benzo[b] thiophenes with 2-methoxy-N-acyl-piperidines and morpholines gave very low yields of the 2-(2'-benzo[b] furanyl)-, and 2-(2'-benzo[b] thienyl) piperidine derivatives. The amidoalkyl
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::76575a983cf040eac635865cd26157aa
https://doi.org/10.1002/bscb.19850940108
https://doi.org/10.1002/bscb.19850940108
Nuclear magnetic resonance study of the sodium salt of mutalomycin, a structural analog of lonomycin
Publikováno v:
Bulletin des Sociétés Chimiques Belges. 97:751-760
The complete assignment of the proton NMR spectrum of the sodium salt of mutalomycin in chloroform was obtained by applying homo- and heteronuclear shift correlation techniques. From the observed chemical shifts and coupling constants the conformatio
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::1ec7bfab030dc34a0c861c8a4cce29bd
https://doi.org/10.1002/bscb.19880971004
https://doi.org/10.1002/bscb.19880971004
Publikováno v:
Bulletin des Sociétés Chimiques Belges. 94:51-57
Anodic methoxylation of 4-methyl-and 4-t.butyl-N-trifluoroacetyl-piperidine results in a 4:1 mixture of the trans-and cis-2-methoxy derivatives. The isomeric 4-methyl derivatives can be separated on a preparative scale by gas chromatography, while th
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::59f06c108234a129978c46ae91461754
https://doi.org/10.1002/bscb.19850940109
https://doi.org/10.1002/bscb.19850940109
Autor:
Frans Borremans, Marc J. O. Anteunis
Publikováno v:
Bulletin des Sociétés Chimiques Belges. 85:681-696
The conformational behaviour of the halomethyl group in 5-position in 1,3-dioxanes is determined quantitatively by low temperature nuclear magnetic resonance, and the origin of the axial preference of ca. 1 kcal.mole−1 relative to the 5-methyl grou
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::ca98daf9669c5b4296bd5a59e36c66a5
https://doi.org/10.1002/bscb.19760850908
https://doi.org/10.1002/bscb.19760850908
Publikováno v:
Bulletin des Sociétés Chimiques Belges. 94:413-419
From 1 H NMR parameters we demonstrate that the cyclic dipeptides derived from L-pipecolic acid and L-γ-thiapipecolic acid with glycine or sarcosine are negatively buckled. The degree of folding of the diketopiperazine ring increases in the γ-thia-
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::78a1f28aa1cdb0f05839b8d29100ef2d
https://doi.org/10.1002/bscb.19850940608
https://doi.org/10.1002/bscb.19850940608