**6. Conclusions**

Camphor and silver derivatives have been used since ancient times as medicines. Although their combination in complexes and the search for their antimicrobial activities only started recently, there is no application of silver camphor imine complexes in medicine, pharmacy, or industry. The results obtained until now show that some silver camphor imine complexes combine antimicrobial activity against bacteria and fungi with cytotoxic activity [42–44]. This feature is highly relevant since opportunistic bacteria and fungi usually develop during cancer treatments due to the immunosuppressive effects of anticancer drugs.

The insights already made into the antimicrobial properties of some silver camphor imine complexes show they have moderate to high antibacterial activity, depending on the characteristics of the ligands. Such information fosters further enhancement of the ligands to optimize the antibacterial properties of the camphor imine complexes. Meanwhile, synthetic strategies to synthesize, characterize, and evaluate the antimicrobial properties of silver camphor imine complexes were developed and described in the present minireview. Detailed knowledge of the bacterial targets of these compounds is still missing, and therefore, future work will focus on the unveiling of the molecular targets and mechanisms underlying their antimicrobial activity. To address these issues, studies will focus on the use of transcriptomic approaches to gain clues regarding the bacterial gene expression responses to exposure to inhibitory concentrations of silver camphor imine complexes. It will be also necessary to use more classical biochemical approaches to identify the bacterial targets of these complexes. The comprehensive knowledge of the molecular details of the antimicrobial activity of silver camphor imine complexes is expected to enable the exploitation of structure and activity relationships to tailor complexes with enhanced antimicrobial activity.

**Author Contributions:** Conceptualization, J.H.L., M.F.N.N.C.; Writing-Original Draft Preparation, J.H.L., M.F.N.N.C., S.A.S., S.A.L.; Writing-Review & Editing, J.H.L., M.F.N.N.C., S.A.S.; Funding Acquisition, J.H.L., M.F.N.N.C.

**Funding:** This research was funded by from FCT-Fundação para a Ciência e a Tecnologia (Portugal) through projects UID/QUI/00100/2013, UID/BIO/04565/2013, Programa Operacional Regional de Lisboa 2020 (Project N. 007317) and the NMR Network (IST-UTL Node) for facilities.

**Acknowledgments:** S.A.S. acknowledges a postdoctoral gran<sup>t</sup> from FCT (SFRH/BPD/102006/2014).

**Conflicts of Interest:** The authors declare no conflict of interest.
