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A high-performance liquid chromatographic method is reported for the resolution of the enantiomers of a series of fused γ-lactams (2,7-diaza-3-oxo[3.3.0]octan-6-ones) with probable anti-HIV and anticancer activity. Resolution was achieved on a Chiralcel® OD column, cellulose tris-(3,5-dimethylphenyl carbamate) adsorbed on macroporous silica gel; mixtures ofn-hexane and isopropyl alcohol in different proportions were used as the mobile phase. The analysis was studied at different temperatures.

The crystal structures of 3-aminomethyl-1,2,4-benzothiadiazine-1, 1-dioxide (1) and 6-aminomethyl-3-methyl-1,2,4-benzothiadiazine-1,1-dioxide hydrochloride monohydrate (2) have been determined by X-ray crystal data. The benzothiadiazine ring is planar in (1), owing to space-group requirements, and almost planar in (2) with the sulfonyl group perpendicular to the rings. The isomer 4H is peculiar to structure, (2) while (1) contains both the 2H and the 4H isomers. In compound (1) the 4H isomers are connected in pairs through hydrogen bonding [N(4)-H(4)?N(3)I 1.88(8) Å], while compound (2) is dominated by a network of hydrogen bonding involving mainly the protonated N(3) nitrogen, the crystallized water molecule and the chlorine.

The crystal structure of taurocyamine has been determined by single-crystal diffraction methods. The compound crystallizes in the monoclinic space groupCc witha=5.418(4),b=13.403(9),c=9.533(7) Å,ß=91.26(4)° andZ=4. The structure was solved by direct methods, and refined by least-squares procedures toR=0.027 (Rw=0.034). The molecule is characterized by statistical distribution of the SO3H group proton as well of the C=NH proton, suggesting the presence either of different isomers or, in some percentage, of zwitterions in the crystal. An extensive hydrogen-bond system dominates the structure in the crystal state.

Taurine has been shown to exert many biological effects. Among them, the ability of this amino acid to induce a reduction of arterial blood pressure, when administered intracerebroventricularly (i.c.v.) to mammals, has been established since a long time ago. To gain further information on the structure–activity requirements for taurine's hypotensive effect, the synthesis of 2-methyltaurine (2-aminopropanesulphonic acid) and the asymmetric synthesis of its enantiomers were performed; the enantiomeric purity of (R)- and (S)-2-methyltaurine was assayed by differential scanning calorimetry (DSC) and HPLC. The findings here reported show that the hypotensive effect elicited by the i.c.v. administration of racemate is mainly due to the (S)-enantiomer. The specificity of this effect was proved by the ability of the taurine antagonist TAG (6-aminomethyl-4H-3-methyl-1,2,4-benzothiadiazine 1,1-dioxide) to prevent it.

The hydrophobicity of fifty‐five literature‐known isothiouronium salts such as (I) are determined by 1‐octanol/water partition.

The isothiouronium salts (I) are prepared by procedures know from the literature.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.