OnLine First articles (OLF) are accepted, peer reviewed and proofread articles that are not yet assigned to an issue.

These are early electronic versions of the manuscript that were accepted for publication in the Journal of the Serbian Chemical Society, but have not yet been subjected to the final editing process and publishing procedure applied by the JSCS Editorial Office.

It must be stressed that the manuscripts still have to be subjected to English grammar and syntax corrections, professional editing and authors review of the galley proof before they are published in its final form. Please note that during these publishing processes, many errors may emerge, which could affect the final content of the manuscript and all legal disclaimers applied according to the policies of the Journal.

This issue is an In Memoriam issue dedicated to Professor Peter Pfendt, who passed away on January 14, 2021. Professor Pfendt is considered the founder of the scientific discipline of Envi­ronmental Chemistry in Serbia.

This issue of the Journal of the Serbian Chemical Society is dedi­cated to an accomplished scientist and excellent mentor Academician Slobodan Milo­sav­ljević, Professor Emeritus at the University of Belgrade – Faculty of Chemistry, on the occasion of his 80^th birthday, in honor of his many achievements in chemistry, his contribution to university education, structural instrumental analysis and natural products chemistry at the University of Belgrade.