The antibiotic tetracycline demeclocycline (DMC) was recently reported to rescue α-synuclein (α-Syn) fibril-induced pathology. However, the antimicrobial activity of DMC precludes its po-tential use in long-term neuroprotective treatments. Here, we synthesized a DMC derivative with residual antibiotic activity and improved neuroprotective effects. The molecule, called de-rivative demeclocycline (DDMC), was obtained by the removal of both dimethylamino substitu-ents at position 4 and the reduction of the hydroxyl group at position 12a on ring A of DMC. The modifications strongly diminished its antibiotic activity against Gram-positive and Gram-negative bacteria. Moreover, this compound preserved the low toxicity of DMC in dopaminergic cell lines while improving its ability to interfere with α-Syn amyloid-like aggregation, showing the highest effectiveness of all tetracyclines tested. Likewise, DDMC demonstrated the ability to reduce seeding induced by the exogenous addition of α-Syn preformed fibrils (α-SynPFF ) in ex vitro models and in SH-SY5Y-α-Syn-tRFP cells. In addition, in the presence of DDMC, α-SynPFF were less inflammogenic, as they dampened the release of tumor necrosis factor α (TNF-α) and glutamate by microglial cells compared to control fibrils. Our results suggest that DDMC may be a promising drug candidate for hit-to-lead development and preclinical studies in PD and other synucleinopathies.