id	author	title	date	pages	extension	mime	words	sentence	flesch	summary	cache	txt
iajs-438	Abbas, Sahar F.; Ali, Emad T.; Tomma, Jumbad H.	Synthesis and Characterization of New Heterocyclic Derived from Pyromellitic Dianhydride	2017	13	.pdf	application/pdf	4412	187	66	The FTIR absorption-spectrum of this compound [VI] showed (C=O) amid absorption band at 1690 cm-1 , the spectrum showed many peaks in the region 3367-3178cm-1 which could be attributed to asymmetric and symmetric stretching vibration of NH and NH2 groups besides to 1310cm-1 and 2652 cm-1 due to C=S groups and S-H group , respectively . NaOH ethanol R X Path one Path two ethanol CH3 -C-CH2-C-CH3 O O NH NH C NH2 S NH2 NH C NH2 S Scheme 1 H H Synthesis of asymmetrical diamic acid N,N‾-Bis-(benzothiazol-2-yl) pyromellitamic diacid	cache/iajs-438.pdf	txt/iajs-438.txt