Fluorescent intracellular calcium indicators

• US 4,849,362 A
• Filed: 05/19/1988
• Issued: 07/18/1989
• Est. Priority Date: 05/19/1988
• Status: Expired due to Term

• Current Assignee: Smithkline Beecham Corporation (Smithkline Beecham PLC)
• Original Assignee: Smithkline Beecham Corporation (Smithkline Beecham PLC)
• Inventors: Katerinopoulos, Haralambos E., Muirhead, Katharine A., DeMarinis, Robert M.
• Primary Examiner(s): Schwartz, Richard A.
• Application Number:
  US07/196,654
• Time in Patent Office: 425 Days
• Field of Search: 548/309, 548/181, 548/183, 436/63, 436/79
• US Class Current: 436/63
• CPC Class Codes: C07D 403/06 linked by a carbon chain containing only aliphatic carbon atoms
• CPC Class Codes: C07D 405/06 linked by a carbon chain containing only aliphatic carbon atoms
• CPC Class Codes: C07D 409/06 linked by a carbon chain containing only aliphatic carbon atoms
• CPC Class Codes: C07D 417/06 linked by a carbon chain containing only aliphatic carbon atoms
• CPC Class Codes: G01N 33/84 involving inorganic compounds or pH

Abstract

Invented are new tetracarboxylate compounds which are chelators for calcium ions. Also invented is a useful method of measuring intracellular calcium concentrations using these novel compounds as an optical indicator.

Claims

1. A compound of the formula:

##STR5## in which;

R is hydrogen or acetoxymethyl;

R₁ is methyl or ethyl;

Z is O, S or NH; and

Y is NH or S;

or when R is hydrogen, a sodium, potassium or lithium salt thereof.

2. A compound according to claim 1 in which R is acetoxymethyl.

3. A compound according to claim 1 in which R₁ is methyl.

4. A compound according to claim 1 in which R₁ is methyl, Z is 0 and Y is NH.

5. A compound according to claim 2 in which R₁ is methyl.

6. A compound according to claim 2 in which R₁ is methyl, Z is O and Y is NH.

7. A method of determining intracellar calcium concentration in intact cells via an optical measurement system which comprises treating said cells with a sufficient quantity of a compound of claim 1 to act as an optical indicator.

8. A method of claim 7 in which flow cytometry or quantitative fluorescence microscopy is used to measure intracellular calcium concentrations.