Customs exemption scope expanded to include amino penicillinic acid within ethyleneamines list, altering tariff notification coverage. The Central Government amended a Customs tariff exemption notification by substituting the listed chemical items so that ethylenediamine, diethylenetriamine, triethylenetetramine, polyamines and 6-Amino Pencillinic Acid (6-APA) are expressly included, thereby expanding the class of goods covered by the existing exemption.