چكيده فارسي :
The synthesis of pyrimido[2,1-b]benzothiazole derivatives has been considered of
greatinterest to organic chemists because oftheir potent and significant pharmacological
activities.1In view of the importance of pyrimido[2,1-b]benzothiazoles, the development of
effective strategies for the synthesis of these fused heterocyclic compounds will be interesting
in both organic synthesis and medicinal chemistry. A common synthetic approach to
pyrimido[2,1-b]benzothiazole derivatives involves three component condensation of 2-amino
benzothiazole, aldehydes and β-ketoesters [2, 3].
Considering the new trends of science and technology towards using natural materials such
as cellulose, the research efforts on green and eco-friendly methods have become popular and
desirable. Cellulose is one of the most abundant natural carbon based biopolymers containing
free OH groups with nucleophilic character.In this work, we have investigated about
preparation of nano-cellulose by sulfuric acid hydrolysis of cotton (purest, cheap and readily
available source of cellulose) and synthesis of TiCl4/nano-cellulose by bonding TiCl4 to OH
groups of D-glucose units in nano-cellulose. TiCl4/nano-cellulose was characterized by FTIR,
FESEM, XRF, EDX and XRD techniques and used as a new, biodegradable, inexpensive
and eco-friendly bio-based catalyst for One-Pot synthesis of pyrimido[2,1-b]benzothiazoles
via three component reaction of aldehydes, ethyl acetoacetate and 2-amino benzothiazole
under thermal condition (Figure 1).
