Thiourea Hydrochloride Research Articles

Sensitive Sensor for Mercury Ion in Aqueous Solution by "Naked-eye" and Fluorescence Recognition

A sensitive and selective Nile blue-based optical sensor 1-benzoyl-3-{2-[9-(ethylamino)-10-methyl-9H-benzo[α]phenoxazin-5-ylamino]ethyl}thiourea hydrochloride(NBET) in aqueous solution for Hg2+ was synthesized.The maximum absorption peak of the probe molecule appeared at 640 nm,and decreased upon the addition of Hg2+ in 0.05 mol/L Tris-HCl buffer solution at pH=7.4,a new peak of absorption at 556 nm was observed.The color of the solution changed from light blue to light purple.There was neglectable change upon the addition of other metal ions.Fluorescence monitoring revealed a fluorescence quenching of the probe's characteristic emission at 660 nm upon the addition of Hg2+.The probe possessed the advantages of near-infrared excitation and emission and high fluorescence quantum yield in aqueous solution and offer an opportunity to detect Hg2+ by a naked-eye manner.Limit of detection of fluorescence spectral for Hg2+ was found to be 0.005 μmol/L in aqueous solution.

Asymmetric synthesis of (+)-trachyspic acid

Aldol reaction of di-tert-butyl 4-(4-methoxybenzyloxy)-2-oxobutanoate with pent-4-enal using (S)-1-(3,5-bis(trifluoromethyl)phenyl)-3-(pyrrolidin-2-ylmethyl)thiourea hydrochloride as a catalyst, followed by Pinnick oxidation and tert-butyl esterification, gave (2S,3S)-di-tert-butyl 2-(2-(4-methoxybenzyloxy)ethyl)-3-allyl-2-hydroxysuccinate in high optical purity (85% ee), from which the total synthesis of (+)-trachyspic acid, a tumor cell heparanase inhibitor, was accomplished.

Phenethylthiazolylthiourea (PETT) compounds as a new class of HIV-1 reverse transcriptase inhibitors. 2. Synthesis and further structure-activity relationship studies of PETT analogs.

Phenylethylthiazolylthiourea (PETT) derivatives have been identified as a new series of non-nucleoside inhibitors of HIV-1 RT. Structure-activity relationship studies of this class of compounds resulted in the identification of N-[2-(2-pyridyl)ethyl]-N'-[2-(5-bromopyridyl)]-thiourea hydrochloride (trovirdine; LY300046.HCl) as a highly potent anti-HIV-1 agent. Trovirdine is currently in phase one clinical trials for potential use in the treatment of AIDS. Extension of these structure-activity relationship studies to identify additional compounds in this series with improved properties is ongoing. A part of this work is described here. Replacement of the two aromatic moieties of the PETT compounds by various substituted or unsubstituted heteroaromatic rings was investigated. In addition, the effects of multiple substitution in the phenyl ring were also studied. The antiviral activities were determined on wild-type and constructed mutants of HIV-1 RT and on wild-type HIV-1 and mutant viruses derived thereof, Ile100 and Cys181, in cell culture assays. Some selected compounds were determined on double-mutant viruses, HIV-1 (Ile 100/Asn103) and HIV-1 (Ile100/Cys181). A number of highly potent analogs were synthesized. These compounds displayed IC50's against wild-type RT between 0.6 and 5 nM. In cell culture, these agents inhibited wild-type HIV-1 with ED50's between 1 and 5 nM in MT-4 cells. In addition, these derivatives inhibited mutant HIV-1 RT (Ile 100) with IC50's between 20 and 50 nM and mutant HIV-1 RT (Cys 181) with IC50's between 4 and 10 nM, and in cell culture they inhibited mutant HIV-1 (Ile100) with ED50's between 9 and 100 nM and mutant HIV-1 (Cys181) with ED50's between 3 and 20 nM.

ChemInform Abstract: Synthesis of 2‐Amino‐4‐imino‐4,5‐dihydrothiazoles from N‐Sulfonyl‐α‐chloroamidines and Thiourea.

AbstractThe chloroamidine hydrochlorides (III), prepared from chloroacetonitrile (I), are N‐tosylated, yielding the N‐sulfonyl‐α‐chloroamidines (V).

Synthesis of 2‐amino‐4‐imino‐4,5‐dihydrothiazoles from N‐sulfonyl‐α‐chloroamidines and thiourea

AbstractA number of new and interesting 2‐amino‐4‐(N‐substituted)imino‐4,5‐dihydrothiazoles were synthesized by reacting thiourea (or thiourea hydrochloride) with N‐alkyl‐ or N,N‐dialkyl‐N′‐p‐toluenesulfonyl‐α‐chloroacetamidines, where the N,N‐alkyl groups were ethyl, cyclohexyl, benzyl, β‐phenethyl, (3,5‐dimethyl‐1‐adamantyl)‐methyl, as well as N,N‐dimethyl‐ and N,N‐pentamethylene. Reactions of N‐alkyl‐N‐p‐toluenesulfonyl‐2‐chloroacetamidines (substituents being N‐ethyl, N‐benzyl and N,N‐dimethyl) with thiourea hydrochloride in hot 2‐propanol furnished 2‐amino‐4‐(p‐toluenesulfonyl)imino‐4,5‐dihydrothiazole (in 51, 60 and 65% yields, respectively) and the corresponding amine hydrochloride. In hot acetone or butanone, the reactions of these N‐sulfonyl‐2‐chloroacetamidines with excess thiourea provided 2‐amino‐4‐N‐(alkyl or N,N‐dialkyl)imminium‐4,5‐dihydrothiazole chlorides in 25–80% yield. The by‐product from these reactions was p‐toluenesulfonamide. The structures of the products were established by chemical transformations and spectral methods (nmr and mass spectra).