[pi] in poly(oxazines
) and demonstrated that such bonds contribute to the improvement of their thermal properties, such as elevated glass transition temperatures [18-20].
The high quantum yield of fluorescence was reported for laser organic dyes (xanthenes, oxazines
, 7-aminocoumarins) .
 and quinazolines  are natural products which exhibit a widespread spectrum of biological activity including antitumor [16-18], anti-inflammatory , and antiplatelet  properties.
Among the topics are organic building blocks for molecular engineering, the design and synthesis of organic molecules for molecular electronics, molecular storage systems for solar thermal energy storage and conversion, strategies to switch fluorescence with photochromic oxazines
, recognizing carbohydrates, the synthesis and function of cyclodextrin-based artificial enzymes, and dendrimers in biology and nanomedicine.
Antimalarial dyes revisited: Xanthenes, Azines, Oxazines
, and Thiazines.
Koycii, "Synthesis of new 1,3-disubstituted-2,3-dihydro-1H-naphth- [1,2e][1,3] oxazines
," Molecules, vol.
Additionally, the polymerization of N-allyl groups at lower temperature (17) before the ring-opening polymerization of oxazines
lead to a mild crosslinking state which would affect the mobility of reaction functional groups, which also could resulted in a higher E.
The large numbers of biologically active molecules that contain the oxazine
nucleus has play important roles in the drug discovery process and exhibit various biological activities [1, 2].
The reaction involves the use of a di-functional phenolic derivative and diamine, producing a linear polymer that contains oxazine
rings in its main-chain .
FTIR (KBr): v = 1498 (tri-substituted phenyl group); 1231 (s; [v.sub.as] (C-O-C of benzoxazine ring)), 1016 (s; [v.sub.s] (C-O-C of benzoxazine ring)); 1085 (s; vas (Si-O-C)); 931 (oxazine
According to Wang and Ishida 2000, the polymerization occurred at oxazine
structure via ring opening influence by distortion of its semichair structure above and below benzene ring plane.
1), the characteristic resonances of oxazine
ring at 3.97 and 4.84 ppm belonging to the -C[H.sub.2]-N--and 0-C[H.sub.2]-N- protons, respectively, were observed.