Does CIP Nomenclature Adequately Handle Molecules with Multiple Stereoelements? A Case Study of Vancomycin and Cognates

Nicolaou, K. C.; Boddy, Christopher N.; Siegel, Jay S.

doi:10.1002/1521-3773(20010216)40:4<701::aid-anie7010>3.0.co;2-o

Cited by 22 publications

(2 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…cyclophanes, are interconverted by rotation of the handle around the planar phenylene. Similar to ansa-compounds 23 the assignment of the stereochemical descriptor can be made as follows in agreement with the CIP rules 25 , 26 : (1) identification of the main cycle 27 – 29 with the preferred directionality (Fig. 1g , from N to C terminus), (2) assignment of the leading atom/group of the bridge (Fig.…”

Section: Resultsmentioning

confidence: 69%

The occurrence of ansamers in the synthesis of cyclic peptides

et al. 2022

View full text Add to dashboard Cite

Abstractα-Amanitin is a bicyclic octapeptide composed of a macrolactam with a tryptathionine cross-link forming a handle. Previously, the occurrence of isomers of amanitin, termed atropisomers has been postulated. Although the total synthesis of α-amanitin has been accomplished this aspect still remains unsolved. We perform the synthesis of amanitin analogs, accompanied by in-depth spectroscopic, crystallographic and molecular dynamics studies. The data unambiguously confirms the synthesis of two amatoxin-type isomers, for which we propose the term ansamers. The natural structure of the P-ansamer can be ansa-selectively synthesized using an optimized synthetic strategy. We believe that the here described terminology does also have implications for many other peptide structures, e.g. norbornapeptides, lasso peptides, tryptorubins and others, and helps to unambiguously describe conformational isomerism of cyclic peptides.

show abstract

Section: Resultsmentioning

confidence: 69%

The occurrence of ansamers in the synthesis of cyclic peptides

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Helical descriptors, however, are considered rather conformational elements of stereogenicity within the CIP nomenclature, which adds extra confusion in naming complex structures. In contrast, the R/S notation often provides unambiguous configuration of chiral axes …”

mentioning

confidence: 99%

Adding Only One Priority Rule Allows Extending CIP Rules to Supramolecular Systems

Alkorta

Elguero

Cintas³

2015

Chirality

View full text Add to dashboard Cite

There are frequent situations both in supramolecular chemistry and in crystallography that result in stereogenic centers, whose absolute configuration needs to be specified. With this aim we propose the inclusion of one simple additional rule to the Cahn‐Ingold‐Prelog (CIP) system of priority rules stating that noncovalent interactions have a fictitious number between 0 and 1. Chirality 27:339–343, 2015. © 2015 Wiley Periodicals, Inc.

show abstract

Fundamental Symmetries and Symmetry Violations from High Resolution Spectroscopy

Qüack¹

2011

Handbook of High‐resolution Spectroscopy

160

View full text Add to dashboard Cite

After an introductory survey, we introduce the seven fundamental symmetries of physics in relation to the group of the molecular Hamiltonian and the current standard model of particle physics (SMPP). We discuss the relation of these symmetries to conservation laws and fundamentally nonobservable properties of nature with the example of parity violation. The particular importance of experiments on detecting symmetry breakings is outlined and the three distinct, basic concepts of symmetry breaking (spontaneous, de facto, de lege) are illustrated with the example of space inversion symmetry breaking and parity violation in chiral molecules. Similar conceptual situations are found for our understanding of the underlying physics of molecular chirality by various types of symmetry breakings, of the evolution of biomolecular homochirality and of irreversibility as breaking of time reversal symmetry. The current status of the quantitative theory of molecular parity violation in the framework of electroweak quantum chemistry is reviewed, including the change of order of magnitude, which was found in recent years and has since been confirmed repeatedly.The concepts of high-resolution spectroscopic experiments on parity violation in chiral molecules are discussed and the status of current attempts toward detecting molecular parity violation is summarized with particular emphasis on the possibilities of measuring timedependent parity violation in the exceptional (still hypothetical) unstable parity isomers of chiral molecules. The concept of successive symmetry breakings in the quantum dynamics of molecules is illustrated with the wide range of time-scales for symmetry-breaking processes ranging from femtoseconds in experiments on very fast intramolecular vibrational redistribution (IVR) to the theoretical times of seconds for molecular parity violation.The role of approximate symmetries and conservation laws for our understanding of selection rules in spectroscopy and in chemical reaction dynamics is analyzed in some detail with the example of approximate parity and nuclear spin symmetry conservation in radiative and reactive molecular processes. This includes the use of permutation-inversion symmetry groups in applications to spectroscopy and state-selected chemical reactions. Statistical concepts for the description of molecular energy levels are presented for use in highresolution spectroscopy and chemical reactions in relation to symmetry properties.We conclude with a summary of the current status of the following symmetries and their violations in spectroscopy and molecular dynamics: nuclear spin symmetry in chemical processes, space inversion symmetry and parity violation in chiral molecules, time reversal symmetry in intramolecular processes, and combined charge conjugation, parity, and time reversal (CPT) symmetry in relation to more fundamental aspects of time reversal and speculations on mass differences in chiral molecules and chiral neutrinos and their antimatter counterparts.

show abstract

Does CIP Nomenclature Adequately Handle Molecules with Multiple Stereoelements? A Case Study of Vancomycin and Cognates

Cited by 22 publications

References 32 publications

The occurrence of ansamers in the synthesis of cyclic peptides

The occurrence of ansamers in the synthesis of cyclic peptides

Adding Only One Priority Rule Allows Extending CIP Rules to Supramolecular Systems

Fundamental Symmetries and Symmetry Violations from High Resolution Spectroscopy

Contact Info

Product

Resources

About