Abstract:
The research work reported in the thesis comprises two parts. In the first part the
reaction of ortho-phthaldehyde with urea, thiourea and their N-alkyl/aryl derivatives is
conducted in acidic and basic media. The resulting chromogens and non-chromogens
compounds are separated by physical, chemical and various kinds of chromatographic
techniques and structure are elucidated by all means of spectroscopy and a single X-ray
crystallography. After identification of compounds, the methods for the determination of
urea present in biological samples are worked out; this will help in modification of
existing clinical techniques used for exact diagnosis of various diseases. Biological
properties of the compounds (isoindolines, benzodiazepines and isobenzofuran) obtained
from the above said reactions are evaluated.
In the second part of the thesis functionalised diarylcarbenes are synthesized which
are excellent reactive intermediates suitable for the direct surface modification of organic
polymers which are in fact used to introduce urea and thiourea functions onto polystyrene
at loading levels of up to 2.3 x 1013 molecules/cm2. Surface modification is confirmed by
different spectral and non-spectral techniques (ATR-IR, XPS & elemental analysis). The
moidifed polymers are capable of reversible binding and release of peroxide at loading
levels of up to 0.6 mmol/g, and polymers display biocidal activity against a spectrum of
Gram-positive and Gram-negative bacteria.
