Methods of using optical agents

1. A process for using a fluorescent agent in a surgical procedure, the process comprising:

administering a renally excretable fluorescent agent into the bloodstream of a patient, wherein the renally excretable fluorescent agent is a pyrazine molecule, wherein the pyrazine molecule is a compound of Formula 7, and

X 1 and X 2 are each independently selected from the group consisting of —CN, —CO 2 R 1 , —CONR 2 R 3 , —NO 2 , —SOR 5 , —SO 2 R 6 , —SO 2 OR 7 and —PO 3 R 8 R 9 ;

Y 1 and Y 2 are each independently selected from the group consisting of —OR 19 , —SR 11 , —NR 12 R 13 , —N(R 14 )COR 15 and Formula A;

Z 1 is selected from the group consisting of a direct bond, —CR 16 R 17 —, —O—, —NR 18 —, —NCOR 19 —, —S—, —SO— and —SO 2 —;

m and n are integers from 1 to 6;

R 1 to R 19 are any suitable substituents capable of enhancing biological and/or physicochemical properties of the pyrazine molecule;

irradiating a ureter of the patient's renal system with infrared radiation, visible radiation, ultraviolet radiation or combinations thereof to excite the agent in the patient's urine and cause the agent to fluoresce; and

detecting the agent's fluorescence in the irradiated ureter to demarcate the position of the ureter and distinguish the ureter from the surrounding tissue during the surgical procedure, wherein the surgical procedure is selected from an abdominal surgery and a pelvic surgery.

2. The process of claim 1 , wherein R 1 to R 19 are each independently selected from the group consisting of hydrogen, carboxylate, sulfonate, sulfate, phosphonate, phosphate, hydroxyl, carboxyl, sulfonyl, sulfonato, and phosphonato.

3. The process of claim 1 , wherein the pyrazine molecule of Formula is selected from the group consisting of 3,6-dicyano-2,5-[(N,N,N′,N′-tetrakis(carboxymethyl)aminolpyrazine, 3,6-[(N,N,N′,N′-tetrakis(2-hydroxyethyl)amino]pyrazine-2,5-dicarboxylic acid, 3,6-bis(N-azatedino)pyrazine-2,5-dicarboxylic acid, 3,6-bis(N-morpholino)pyrazine-2,5-dicarboxylic acid, 3,6-bis(N-piperazino)pyrazine-2,5-dicarboxylic acid, 3,6-bis(N-thiomorpholino)pyrazine-2,5-dicarboxylic acid, 3,6-bis(N-thiomorpholino)pyrazine-2,5-dicarboxylic acid S-oxide, 2,5-dicyano-3,6-bis(N-thiomorpholino)pyrazine S,S-dioxide, 3,6-diaminopyrazine-2,5-dicarboxylic acid, and pharmaceutically acceptable formulation thereof.

4. The process of claim 1 , wherein the pyrazine molecule is administered by a route selected from the group consisting of parenterally, enterally, intravenously, intraarterially, orally, gastric or intestinal feeding tube, intramuscular injection, subcutaneous injection or infusion, intraperitoneal injection or infusion, intrathecally, sublingually, rectally, vaginally, nasally, by inhalation, transdermal absorption through the skin and intraosseous infusion.

5. The process of claim 4 , wherein the pyrazine molecule is administered intravenously.

6. The process of claim 1 , wherein the pyrazine molecule is detected using at least one of unaided eye, camera, charged coupled device, photomultiplier tube, avalanche diode, and photodiodes.

7. The process of claim 1 , wherein the surgical procedure is selected from the group consisting of total or partial hysterectomy, oophorectomy, tubal ligation, surgical removal of ovarian cysts, anterior repair of the vaginal wall, caesarean section, repair of a pelvic prolapse, pelvic mass resection, removal of a fallopian tube, adnexectomy, removal of an ectopic pregnancy, vasectomy, prostatectomy, hernia repair surgery, colectomy, cholecystectomy, appendectomy, hepatobiliary surgery, splenectomy, distal or total pancreatectomy, the Whipple procedure, and abdominal or pelvic lymphadenectomy.

8. The process of claim 1 , wherein the pharmaceutically acceptable formulation comprises one or more excipients selected from the group consisting of buffers, electrolytes, diluents, solvents, antimicrobial agents, chelating agents, preservatives, surfactants, thixotropic agents, flavoring agents, binders, fillers, disintegrants, lubricants, sweeteners, and combinations thereof.

9. A process for using a fluorescent agent in a surgical procedure, the process comprising:

irradiating a surgical field of a patient undergoing an abdominal surgery with infrared radiation, visible radiation, ultraviolet radiation or combinations thereof to excite a renally excretable fluorescent agent in the patient's urine and cause the agent to fluoresce, which is located in a ureter of the patient's renal system in the surgical field during the irradiating, wherein the renally excretable fluorescent agent is a pyrazine molecule, wherein the pyrazine molecule is a compound of Formula 7, and

X 1 and X 2 are each independently selected from the group consisting of —CN, —CO 2 R 1 , —CONR 2 R 3 , —NO 2 , —SOR 5 , —SO 2 R 6 , —SO 2 OR 7 and —PO 3 R 8 R 9 ;

Y 1 and Y 2 are each independently selected from the group consisting of —OR 19 , —SR 11 , —NR 12 R 13 , —N(R 14 )COR 15 and Formula A;

Z 1 is selected from the group consisting of a direct bond, —CR 16 R 17 —, —O—, —NR 18 —, —NCOR 19 —, —S—, —SO— and —SO 2 —;

m and n are integers from 1 to 6;

R 1 to R 19 are any suitable substituents capable of enhancing biological and/or physicochemical properties of the pyrazine molecule; and

surgically manipulating a tissue of the patient based, at least in part, on optical detection of the agent's fluorescence in the ureter and distinguishing the ureter from the surrounding tissue during the abdominal surgery.

10. The process of claim 9 , wherein R 1 to R 19 are each independently selected from the group consisting of hydrogen, carboxylate, sulfonate, sulfate, phosphonate, phosphate, hydroxyl, carboxyl, sulfonyl, sulfonato, and phosphonato.

11. The process of claim 9 , wherein the pyrazine molecule of Formula is selected from the group consisting of 3,6-dicyano-2,5-[(N,N,N′,N′-tetrakis(carboxymethyl)aminolpyrazine, 3,6-[(N,N,N′,N′-tetrakis(2-hydroxyethyl)amino]pyrazine-2,5-dicarboxylic acid, 3,6-bis(N-azatedino)pyrazine-2,5-dicarboxylic acid, 3,6-bis(N-morpholino)pyrazine-2,5-dicarboxylic acid, 3,6-bis(N-piperazino)pyrazine-2,5-dicarboxylic acid, 3,6-bis(N-thiomorpholino)pyrazine-2,5-dicarboxylic acid, 3,6-bis(N-thiomorpholino)pyrazine-2,5-dicarboxylic acid S-oxide, 2,5-dicyano-3,6-bis(N-thiomorpholino)pyrazine S,S-dioxide, 3,6-diaminopyrazine-2,5-dicarboxylic acid, and pharmaceutically acceptable formulation thereof.

12. A process for using a fluorescent agent in a surgical procedure, the process comprising:

administering a renally excretable fluorescent agent into the bloodstream of a patient, wherein the renally excretable fluorescent agent is a pyrazine molecule, wherein the pyrazine molecule is a compound of Formula 7, and

X 1 and X 2 are each independently selected from the group consisting of —CN, —CO 2 R 1 , —CONR 2 R 3 , —NO 2 , —SOR 5 , —SO 2 R 6 , —SO 2 OR 7 and —PO 3 R 8 R 9 ;

Y 1 and Y 2 are each independently selected from the group consisting of —OR 19 , —SR 11 , —NR 12 R 13 , —N(R 14 )COR 15 and Formula A;

Z 1 is selected from the group consisting of a direct bond, —CR 16 R 17 —, —O—, —NR 18 —, —NCOR 19 —, —S—, —SO— and —SO 2 —;

m and n are integers from 1 to 6;

R 1 to R 19 are any suitable substituents capable of enhancing biological and/or physicochemical properties of the pyrazine molecule;

irradiating a ureter of the patient with infrared radiation, visible radiation, ultraviolet radiation or combinations thereof to excite the agent and cause the agent to fluoresce;

subsequent to the administering, detecting the agent's fluorescence based, at least in part, on the irradiating; and

determining if the agent is retained in the urine within the ureter based, at least in part, on the detecting fluorescence.

13. The process of claim 12 , wherein R 1 to R 19 are each independently selected from the group consisting of hydrogen, carboxylate, sulfonate, sulfate, phosphonate, phosphate, hydroxyl, carboxyl, sulfonyl, sulfonato, and phosphonato.

14. The process of claim 12 , wherein the pyrazine molecule of Formula is selected from the group consisting of 3,6-dicyano-2,5-[(N,N,N′,N′-tetrakis(carboxymethyl)aminolpyrazine, 3,6-[(N,N,N′,N′-tetrakis(2-hydroxyethyl)amino]pyrazine-2,5-dicarboxylic acid, 3,6-bis(N-azatedino)pyrazine-2,5-dicarboxylic acid, 3,6-bis(N-morpholino)pyrazine-2,5-dicarboxylic acid, 3,6-bis(N-piperazino)pyrazine-2,5-dicarboxylic acid, 3,6-bis(N-thiomorpholino)pyrazine-2,5-dicarboxylic acid, 3,6-bis(N-thiomorpholino)pyrazine-2,5-dicarboxylic acid S-oxide, 2,5-dicyano-3,6-bis(N-thiomorpholino)pyrazine S,S-dioxide, 3,6-diaminopyrazine-2,5-dicarboxylic acid, and pharmaceutically acceptable formulation thereof.