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Upstream product

• 5053-24-7 2-methylthio-1,3-thiazole 
• 74-88-4 methyl iodide 
• 5685-07-4 1,3-thiazoline-2-thione 

Relevant academic research and scientific papers

Synthesis and antileishmanial evaluation of thiazole orange analogs

Cyanine compounds have previously shown excellent in vitro and promising in vivo antileishmanial efficacy, but the potential toxicity of these agents is a concern. A series of 22 analogs of thiazole orange ((Z)-1-methyl-4-((3-methylbenzo[d]thiazol-2(3H)-ylidene)methyl)quinolin-1-ium salt), a commercial cyanine dye with antileishmanial activity, were synthesized in an effort to increase the selectivity of such compounds while maintaining efficacy. Cyanines possessing substitutions on the quinolinium ring system displayed potency against Leishmania donovani axenic amastigotes that differed little from the parent compound (IC50 12–42 nM), while ring disjunction analogs were both less potent and less toxic. Changes in DNA melting temperature were modest when synthetic oligonucleotides were incubated with selected analogs (ΔTm ≤ 5 °C), with ring disjunction analogs showing the least effect on this parameter. Despite the high antileishmanial potency of the target compounds, their toxicity and relatively flat SAR suggests that further information regarding the target(s) of these molecules is needed to aid their development as antileishmanials.

Specific Molecular Orbital Contributions to Nucleophilicity. The Thiocarbonyl Group as Privileged Monitor To Pinpoint Active and Less Active Molecular Orbitals in Reactions with Methylating Agents

The rate constants for 41 compounds bearing a C=S function reacting with MeX (X = I, Tos) span 7 orders of magnitude.The PES spectra of these compounds display two very low energy peaks, which stand clearly apart from the other peaks.These two peaks correspond to the ? orbitals of the C-S group; one is its CS ? bonding orbital oriented out of the molecular plane (?CS) and the other its p-type in-plane lone pair orbital (?S).For some of the compounds, the HOMO is the ?CS orbital and for others the HOMO is the ?S lone pair orbital.The best correlation (R = 0.96) between rate constants k and PES data is obtained when ln(k) is plotted against the inverse of PES energy of the ?S lone pair orbital.Whether this lone pair orbital is the HOMO or the next lower HOMO has no importance.A modest correlation (R = 0.78) is obtained when ln(k) is plotted against the inverse of PES energy of the ?CS bonding orbital.An attempt to correlate the calculated energy of the third highest occupied orbital (from AM1 calculations) with ln(k) provides a complete scattering of data (R S (ca. 90 kcal mol-1 deeper than the HOMO) correlates reasonably with ln(k) (R = 0.88).The energies of the S 2s and 2p core orbitals (calculated for 13 cyclic compounds with the HF/3-21G technique to be 4000 to 5500 kcal mol-1 deeper than HOMO) correlate with ln(k) (R = 0.86) as well as does that of the second lone pair orbital ?S.These results are the first where both frontier orbitals and core orbitals display correlation with overall reactivity.They are discussed in terms of direct (perturbational) versus indirect (nonperturbational) concepts.