1-Chloro-2-formyl indenes and tetralenes have been synthesized using Vilsmeier–Haack–Arnold reaction onto indanones and tetralones. Most of these analogues exhibited antitubercular activity against Mycobacterium tuberculosis H37Rv strain with MICs ranging from 30 to 500 μg/mL. Analogue 13 was further modified to some derivatives. The most active analogue 23 showing MIC at 30 μg/mL was further evaluated