X-Nico

2 unusual facts about covalent bond


Cycloalkyne

A cycloalkyne consists of a closed ring of carbon atoms containing one or more triple bonds.

Relaxase

This means that they use a metal ion to aid the transfer of an ester bond from the DNA phosphodiester backbone to a catalytic tyrosine side chain, resulting in a long-lived covalent phosphotyrosine intermediate that essentially unified the nicked DNA strand and the enzyme as one molecule.


Physalin

Physalins are steroidal constituents of Physalis plants which possess an unusual 13,14-seco-16,24-cyclo-steroidal ring skeleton (where the bond that is normally present between the 13 and 14 positions in other steroids is broken while a new bond between positions 16 and 24 is formed; see figure below).


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