That's because sequential rings of oxygen atoms exactly match the size, and balance the charge, of potassium ions.
Ixabepilone, a second-generation semisynthetic analog of epothilone B has nitrogen substituted at position 16 of the macrolide ring instead of oxygen, making it a lactam [ 34] (Fig. 1).
Iron plays a crucial role in oxygen uptake and transport [as part of the ferrous ring of haemoglobin (Hb ], oxygen storage (as a component of myoglobin), oxygen metabolism, and energy production (as a component of oxidative enzymes and respiratory chain proteins) and is involved in erythropoiesis.
High f− values are associated with the nitrogen atoms of thiadiazole ring and oxygen of the pyrone ring, in addition to oxygen atom of the bridge.
For example, laccases are able to decolorize azo dyes through nonspecific oxidation of aromatic rings in presence of oxygen as an electron acceptor (Chivukula and Renganathan 1995).
The descriptors involved in the building of 2D QSAR model are retention index for six membered rings, total number of oxygen connected with two single bonds, polar surface area excluding P and S plays a significant role in COX-2 inhibition.
The plasma in this doughnut-shaped ring of ionized sulfur, oxygen, sodium, and chlorine originates when neutral atoms in the "cloud" surrounding Io are ionized and carried along by the Jovian magnetosphere.
The pydc coordinated to the Zn II) ions through nitrogen atom of pyrimidine ring and oxygen atom of carboxylate group as a bidentate ligand.
This fragmentation pattern suggested the seven or eight position of the benzene ring as the site of oxygen insertion.
They are named by using the parent name crown preceded by a number describing the size of the ring and followed by the number of oxygen atoms in the ring.
The researched results indicate the addition of oxygen, benzene ring and oxyethyl group would enhance the polarity of surfactant, which induce the increase of interaction between headgroup and water molecule.
