Synthesis of diphenoxyadamantane alkylamines with pharmacological interest

Nascent pharmacological advancement in adamantane derivatives

The adamantane moiety has attracted significant attention since its discovery in 1933 due to its remarkable structural, chemical, and medicinal properties. This molecule has a notable impact in the therapeutic field because of its "add-on" lipophilicity to any pharmacophoric moieties. As in the case of molecular hybridization, in which one pharmacophore is attached to another one(s) with a probability of increasing the biological activity, adding an adamantane unit improves the absorption distribution, metabolism and excretion properties of the resultant hybrid molecule. This review summarizes various reports highlighting the biological activities of adamantane-based synthetic compounds and their structure-activity relationship study. The information presented in this review may open up possible dimensions for adamantane-based drug development and discovery in the pharmaceutical industry after proper structural modifications.

Adamantane-Substituted Purine Nucleosides: Synthesis, Host-Guest Complexes with β-Cyclodextrin and Biological Activity

Purine nucleosides represent an interesting group of nitrogen heterocycles, showing a wide range of biological effects. In this study, we designed and synthesized a series of 6,9-disubstituted and 2,6,9-trisubstituted purine ribonucleosides via consecutive nucleophilic aromatic substitution, glycosylation, and deprotection of the ribofuranose unit. We prepared eight new purine nucleosides bearing unique adamantylated aromatic amines at position 6. Additionally, the ability of the synthesized purine nucleosides to form stable host-guest complexes with β-cyclodextrin (β-CD) was confirmed using nuclear magnetic resonance (NMR) and mass spectrometry (ESI-MS) experiments. The in vitro antiproliferative activity of purine nucleosides and their equimolar mixtures with β-CD was tested against two types of human tumor cell line. Six adamantane-based purine nucleosides showed an antiproliferative activity in the micromolar range. Moreover, their effect was only slightly suppressed by the presence of β-CD, which was probably due to the competitive binding of the corresponding purine nucleoside inside the β-CD cavity.

Probing Adamantane Arylhydroxamic Acids against Trypanosoma brucei and Trypanosoma cruzi

In this work, we present the synthesis and the anti-trypanosomal activity of the 2-(4-(adamant-1-yl)phenyl)-N-hydroxyarylamides, 1a,b and the 2-(4-(adamant-1-yl)phenoxy)-N-hydroxyacetamide, 1c. The 4-(adamant-1-yl)phenyl- and 4-(adamant-1-yl)phenoxy- moieties, which are endowed with promising drug-like properties, are functionalized at the side chain termini as hydroxamic acids. The phenoxy acetohydroxamic derivative, 1c, shows the most interesting profile in terms of activity and toxicity against trypanosomes and merits further investigation.

Synthesis and evaluation of novel 2,4-disubstituted arylthiazoles against T. brucei

2-{2-[3-(1-Adamantyl)-4-fluorophenyl]thiazol-4-yl}ethan-1-amine (1a) and 2-{2-[4-(1-adamantyl)phenyl]thiazol-4-yl}ethan-1-amine (2a) exhibit activity against T. brucei in the range of IC₅₀ = 0.42 μM and IC₅₀ = 0.80 μM, respectively.

The design, synthesis and pharmacological evaluation of the 4-substituted-2-[3-(adamant-1-yl)-4-fluorophenyl]thiazoles 1a–j, the 4-substituted-2-[4-(adamant-1-yl)phenyl]thiazoles 2a–h, the 2-substituted-4-[4-(adamant-1-yl)phenyl]thiazoles 3a–e, the N-substituted 2-phenylthiazol-4-ethylamides 4a, b and the N-substituted 4-phenylthiazol-2-ethylamides 4c, d is described. Compounds 1a and 2a exhibit trypanocidal activity in the range of IC₅₀ = 0.42 μM and IC₅₀ = 0.80 μM, respectively. Both of these derivatives bear a lipophilic end, which consists of a 4-(1-adamantyl) phenyl or a 3-(1-adamantyl)phenyl moiety, a 1,3-thiazole ring and a functional end, which comprises of an alkylamine and can be considered as promising candidates for the treatment of Trypanosoma brucei infections.

Synthesis, biology, computational studies and in vitro controlled release of new isoniazid-based adamantane derivatives

Aim: There is a necessity for new drugs to be more efficient than today's standard due to the emergence of drug-resistant strains of Mycobacterium tuberculosis (Mtb) Results/methodology: 12 new isoniazid-based adamantane derivatives were synthesized and tested for their antitubercular activity. The pharmacological test results and the aqueous dissolution profile of representative examples of the new molecules are in agreement with the computational results obtained from docking poses and molecular dynamics simulations on the tested compounds. Conclusion: Among their congeners, the adamantane isonicotinoyl hydrazones Ia and Ih exhibit the best antitubercular activity (MIC = 0.04 μg/ml) and the lowest cytotoxicity (selectivity index ≥2500). These results are useful for in future in vivo studies.

Synthesis and Evaluation of Nifurtimox-Adamantane Adducts with Trypanocidal Activity

The synthesis and pharmacological evaluation of C1-substituted adamantane hydrazones, their C2-substituted isomers, and C1-substituted adamantane furanoic carboxamides is described. These new adamantane derivatives exhibited an interesting pharmacological profile in terms of trypanocidal activity and selectivity. The most active adduct with the best selectivity in this study was found to be the phenylacetoxy hydrazone 1 b (2-[4-(tricyclo[3.3.1.1^3,7 ]dec-1-yl)phenyl]-N'-[(5-nitrofuran-2-yl)methylene]acetohydrazide; EC₅₀ =11±0.9 nm, SI_Tb =770).