Compounds that regulate quorum sensing in Staphylococcal bacteria and in particular in Staphylococcus aureus are provided. Compounds are described in formulas I, II, III, IV, V and VI herein. One or more compounds herein can be employed to inhibit QS and to thus inhibit virulence in Staphylococcus bacteria and in particular in Staphylococcus aureus. Compounds herein and pharmaceutical compositions containing one or more of these compounds are useful, for example, in treating infections of Staphylococcus bacteria and in particular of Staphylococcus aureus. Methods for treating such bacterial infections are provided.

A phenyleneethynylene macrocycle (PEMC) is constructed that is a cyclic or polycyclic oligo (oligophenyleneethynylene-co-polyamine) where a monodispersed oligophenyleneethynylene is coupled with a polyamine. The PEMC is formed by coupling a monodispersed di-aldehyde end-capped oligophenyleneethynylene with a polyamine to form a macrocyclic imine and reducing the imine to an amine. The PEMC is useful at entering living cells for the fluorescence imaging of the living cells without toxicity to the cells.

A phenyleneethynylene macrocycle (PEMC) is constructed that is a cyclic or polycyclic oligo (oligophenyleneethynylene-co-polyamine) where a monodispersed oligophenyleneethynylene is coupled with a polyamine. The PEMC is formed by coupling a monodispersed di-aldehyde end-capped oligophenyleneethynylene with a polyamine to form a macrocyclic imine and reducing the imine to an amine. The PEMC is useful at entering living cells for the fluorescence imaging of the living cells without toxicity to the cells.

The present invention provides cyclic depsipeptide compounds of formula (I) and compositions comprising the compounds that are effective against parasites that harm animals. The compounds and compositions may be used for combating parasites in or on mammals and birds. The invention also provides for an improved method for eradicating, controlling and preventing parasite infestation in birds and mammals.

The present invention provides cyclic depsipeptide compounds of formula (I) and compositions comprising the compounds that are effective against parasites that harm animals. The compounds and compositions may be used for combating parasites in or on mammals and birds. The invention also provides for an improved method for eradicating, controlling and preventing parasite infestation in birds and mammals.

Provided herein are antibacterial compounds, wherein the compounds in some embodiments have broad spectrum bioactivity. In various embodiments, the compounds act by inhibition of lipoprotein signal peptidase II (LspA), a key protein in bacteria. Pharmaceutical compositions and methods for treatment using the compounds described herein are also provided.

An organic compound having an excellent electron injection and transport performance is provided as a material for a low-power-consumption organic electroluminescent device. A low-power-consumption organic electroluminescent device is also provided by using the compound. The compound is a compound of general formula (1) or (2) having a substituted bipyridyl and triphenylene ring structure. The organic electroluminescent device includes a pair of electrodes, and one or more organic layers sandwiched between the pair of electrodes, and uses the compound as constituent material of at least one of the organic layers. ##STR00001##

The present invention provides cyclic depsipeptide compounds of formula (I) and compositions comprising the compounds that are effective against parasites that harm animals. The compounds and compositions may be used for combating parasites in or on mammals and birds. The invention also provides for an improved method for eradicating, controlling and preventing parasite infestation in birds and mammals.

The present invention provides cyclic depsipeptide compounds of formula (I) and compositions comprising the compounds that are effective against parasites that harm animals. The compounds and compositions may be used for combating parasites in or on mammals and birds. The invention also provides for an improved method for eradicating, controlling and preventing parasite infestation in birds and mammals.

The present invention relates to methods of modulating an immune response mediated by a PD-1 signaling pathway and of treating a cancer or an infectious disease. A subject is administered a compound(s) or a pharmaceutically acceptable salt or pharmaceutically acceptable composition thereof of formula (I)

##STR00001##

In the ring Q is S or O. R.sub.1 substituents are an optionally substituted side chain of the amino acid Ser or Thr and R.sub.3 substituents are a side chain of the amino acids Asn, Asp, Gln, or Glu. R.sub.2 is hydrogen or CO-Aaa and Aaa is Thr or Ser with a free, amidated or esterified C-terminus. R.sub.4 and R.sub.5 are independently hydrogen or absent. R.sub.6 is hydrogen, alkyl or acyl.