US4397779A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of xanthine tracers
Assignee: Baxter International Inc
•
Filing: 1981-05-28
•
Granted: 1983-08-09
•
Expires: 2001-05-28
Abstract
Abstract Compounds useful as tracers in the radioimmunoassay of xanthine derivatives such as theophylline and pharmacologically related drugs: ##STR1## wherein at least one R 1 , R 3 , R 7 or R 8 is a radioiodinated radical and wherein, if not substituted by a radioiodinated radical, the remaining R 1 , R 3 , R 7 or R 8 groups are otherwise identical to the substituents at these positions in the xanthine derivative to be assayed. Ordinarily, R 1 is hydrogen, acetate or methyl; R 3 is methyl; R 7 is hydrogen, acetate or methyl; and R 8 is hydrogen. The tracers are made by linking radioiodinatable or preradioiodinated radicals to the xanthine derivative which is to be assayed. The tracers may be employed in known radioimmunoassay techniques.
Inventors
- 👤 Ernest V. Groman
- 👤 Michael D. Cabelli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 06:10
CPC Classifications
C; C07; C07D; C07D473/00; C07D473/02; C07D473/04; C07D473/06; C07D473/08; G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/531; G01N33/532; G01N33/534; Y; Y10; Y10S; Y10S530/00; Y10S530/806
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
135 words
The method of making a xanthene derivative which comprises (a) providing an alkali metal salt of a compound having the structure ##STR37## wherein at least one R 1 , R 3 or R 7 is hydrogen, and, if not hydrogen, R 1 and R 7 are acetate or methyl and R 3 is methyl; (b) reacting the salt with a lower alkyl ester of an ω-halogenated normal or branched chain alkyl acid ester having the structure ##STR38## wherein R 5 is hydrocarbon; X is halogen; and B is lower alkyl of from 1 to about 7 carbon atoms; (c) hydrolyzing the reaction product to form a free acid; (d) forming a mixed anhydride by reacting the free acid with an activating agent; and (e) condensing the mixed anhydride with an amino-substituted radioiodinated or radioiodinatable compound.
Claim 2
Independent Claim
135 words
The method of making a xanthene derivative which comprises (a) providing an alkali metal salt of a compound having the structure ##STR37## wherein at least one R 1 , R 3 or R 7 is hydrogen, and, if not hydrogen, R 1 and R 7 are acetate or methyl and R 3 is methyl; (b) reacting the salt with a lower alkyl ester of an ω-halogenated normal or branched chain alkyl acid ester having the structure ##STR38## wherein R 5 is hydrocarbon; X is halogen; and B is lower alkyl of from 1 to about 7 carbon atoms; (c) hydrolyzing the reaction product to form a free acid; (d) forming a mixed anhydride by reacting the free acid with an activating agent; and (e) condensing the mixed anhydride with an amino-substituted radioiodinated or radioiodinatable compound.
Claim 3
Dependent Claim
20 words
The method of claim 1 wherein R 5 is substituted with no more than two hydroxy, amino or alkoxy substituents.
Claim 4
Dependent Claim
23 words
The method of claim 1 wherein the amino-substituted radioiodinatable compound is tyrosine, tyrosinol, 4-(2-aminoethyl)phenol, histidine, histidinol, histamine, and polypeptides containing tyrosine or histidine.
Claim 5
Dependent Claim
14 words
The method of claim 1 including the additional step of radioiodinating the xanthine derivative.
Claim 6
Independent Claim
144 words
The method of making a xanthine derivative which comprises (a) providing a starting compound having the structure ##STR39## wherein (i) R 5 is a bond; a cyclic, normal or branched chain alkylene or alkenylene; or such alkylene or alkenylene substituted with halo, hydroxy, keto, alkoxy, alkoxycarbonyl, carboxyl, amino or alkylamino groups; (ii) U is carboxyl or amino; and (iii) R 1 , R 3 and R 7 are identical to the substituents at these positions in the xanthine derivative to be radioimmunoassayed; (b) Providing a radioiodinatable or radioiodinated compound having a carboxyl substituent if U is amino or an amino substituent if U is carboxyl; (c) forming a mixed anhydride by reacting the carboxyl substituent with an activating agent; and (d) condensing the mixed anhydride with the amino substituent to form a peptide bond between the radioiodinatable or radioiodinated compound and the starting compound.
Claim 7
Independent Claim
144 words
The method of making a xanthine derivative which comprises (a) providing a starting compound having the structure ##STR39## wherein (i) R 5 is a bond; a cyclic, normal or branched chain alkylene or alkenylene; or such alkylene or alkenylene substituted with halo, hydroxy, keto, alkoxy, alkoxycarbonyl, carboxyl, amino or alkylamino groups; (ii) U is carboxyl or amino; and (iii) R 1 , R 3 and R 7 are identical to the substituents at these positions in the xanthine derivative to be radioimmunoassayed; (b) Providing a radioiodinatable or radioiodinated compound having a carboxyl substituent if U is amino or an amino substituent if U is carboxyl; (c) forming a mixed anhydride by reacting the carboxyl substituent with an activating agent; and (d) condensing the mixed anhydride with the amino substituent to form a peptide bond between the radioiodinatable or radioiodinated compound and the starting compound.
Claim 8
Dependent Claim
18 words
The method of claim 5 wherein R 5 contains no more than two hydroxy, amino or alkoxy substituents.
Claim 9
Dependent Claim
25 words
The method of claim 5 wherein the amino-substituted radioiodinatable compound is tyramine, tyrosine, tyrosinol, 4-(2-aminoethyl) phenol, histidine, histidinol, histamine, and polypeptides containing tyrosine or histidine.
Claim 10
Dependent Claim
14 words
The method of claim 5 including the additional step of radioiodinating the xanthine derivative.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-08-08 | 1987-02-07 | 1987-08-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-08 | 1991-02-07 | 1991-08-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-08 | 1995-02-07 | 1995-08-09 | $7700.00 | Window Closed / Lapsed |