A robust, regioselective synthesis of 3-amino-1,2,4-triazoles is described. This reaction employs a key intermediate 2, which is coupled to carboxylic acids in good yields to afford intermediates 3a-d. These entities, in turn, react with a variety of hydrazines or hydrazine hydrochlorides to provide

view to work with ts as a function of concentration rather than with the function r'rc/(z,, -zd). In doing such an analysis of z St it should he kept in mind. that the error will usually 1~ a function of concentration and will also be biased toward positive valUeS. This work was sulqxxted by U.S. Ve

Multiple addition is the problem of adding N b-bit integers. Prefix sums and multiple addition play fundamental roles in many algorithms, particularly on the reconfigurable mesh (R-Mesh). Scaling algorithms on the R-Mesh to run with the same or increased efficiency on fewer processors is a challengi

The broad spectrum of biological propertiesI, including antileukemic activity', associated with quassinoid related principles from the plant family Simmubaeeae has attracted considerable interest. 3 Prompted by the suggestion that the conjugated ketone in the A-ring of quassinoids may play an active

Preparation of the spiro beta-lactam 7 and its evaluation as a poliovirus and human rhmovirus 3Cproteinase inhibitor is described. Controlled proteolysis of precursor polypeptides is crucial to the life cycle of picomavirusesl (e.g., human rhinovirus and poliovirus). The replication of many animal

The recent communication by Shani (1) in which the photolysis of cis, cis-cyclodeca---3,8-diene-1, 6-dione (I) is reported to give cis,\*, cis-tricyclo[5. 3. 0. 0 2, (+d ecane-4,9--dione prompts us to report results we had obtained independently which lead to the cis, -anti, cis (IIa) stereochemical

Consider a body of water of ÿnite depth under the in uence of gravity, bounded below by a at, impermeable surface. If viscous and surface tension e ects are ignored, and assuming that the ow is incompressible and irrotational, the uid motion is governed by the Euler equations together with suitable

Single-crystal X-ray study T = 296 K Mean '(C±C) = 0.004 A Ê Disorder in main residue R factor = 0.045 wR factor = 0.143 Data-to-parameter ratio = 15.0 For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e.