Patent US4894468A successfully refreshed from Google Patents.
US4894468A
Expired / Lapsed
US
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Substituted silica
Assignee: Yeda Research and Development Co Ltd
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Filing: 1987-05-01
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Granted: 1990-01-16
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Expires: 2007-05-01
Abstract
Abstract The invention relates to modified silica, substituted with a variety of substituents. There is provided a product termed primary hydroxyl silica where there are attached to the silica substituents bearing a single hydroxyl group. Furthermore there are provided a wide variety of derivatives of such hydroxy-silica, which are of value in affinity chromatography and for various other uses. The products combine the thermal and mechanical stability of the silica used as carrier with the useful properties of the substituents.
Inventors
- 👤 Meir Wilchek
- 👤 Karin Cabrera
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 16:50
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/281; B01J20/286; B01J20/289; B01J20/02; B01J20/10; B01J20/103; B01J20/28; B01J20/28002; B01J20/28004; B01J20/28014; B01J20/28016; B01J20/28019; B01J20/28054; B01J20/28078; B01J20/30; B01J20/3092; B01J20/32; B01J20/3202; B01J20/3204; B01J20/3214; B01J20/3217; B01J20/3219; B01J20/3231; B01J20/3242; B01J20/3244; B01J20/3246; B01J20/3257; B01J20/3259; B01J20/3261; B01J20/3263; B01J20/3268; B01J20/3272; B01J20/3274; B01J2220/00; B01J2220/50; B01J2220/54; B01J2220/58
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
118 words
A compound of the general formula ##STR4## wherein: Alk is lower alkyl and Si is silica, and where: a. the compound is a primary hydroxy silica compound, wherein R is hydroxyl or R is --(CH 2 ) n --O--(CH 2 ) m --CH 2 --OH, b. a derivative thereof wherein: R is --O--(CH 2 ) m --R 1 --OR 2 , R 1 is a group selected from: ##STR5## R 2 is selected from: hydrogen, --CN, --SO 2 CH 2 --CF 3 , ##STR6## where Q is a group --HN--(CH 2 ) n --NH 2 , --HN--(CH 2 ) n --COOH, --HN--peptide or --HN--protein, where n, m and p are small integers, where m may also be zero.
Claim 2
Dependent Claim
118 words
A compound of the general formula ##STR4## wherein: Alk is lower alkyl and Si is silica, and where: a. the compound is a primary hydroxy silica compound, wherein R is hydroxyl or R is --(CH 2 ) n --O--(CH 2 ) m --CH 2 --OH, b. a derivative thereof wherein: R is --O--(CH 2 ) m --R 1 --OR 2 , R 1 is a group selected from: ##STR5## R 2 is selected from: hydrogen, --CN, --SO 2 CH 2 --CF 3 , ##STR6## where Q is a group --HN--(CH 2 ) n --NH 2 , --HN--(CH 2 ) n --COOH, --HN--peptide or --HN--protein, where n, m and p are small integers, where m may also be zero.
Claim 3
Dependent Claim
25 words
A compound according to claim 1, of the formula ##STR7## where Alk designates lower alkyl and where n is an integer from 1 to 5.
Claim 4
Dependent Claim
28 words
A compound according to clam 1, of the formula ##STR8## where R is ##STR9## where m and n are each a small integer of from 1 to 5.
Claim 5
Dependent Claim
28 words
A compound according to clam 1, of the formula ##STR8## where R is ##STR9## where m and n are each a small integer of from 1 to 5.
Claim 6
Dependent Claim
37 words
A compound according to claim 2 or 3, wherein there is provided in said molecule a spacer of the type --HN--(CH 2 ) n --NH-- or --HN--(CH 2 ) n --CO--, where n is a small integer.
Claim 7
Dependent Claim
31 words
Modified silica according to claims 1 to 4, of irregular or spherical particle form, of a pore size in the range of from 3 μm and up to about 200 mm.
Claim 8
Dependent Claim
15 words
Modified silica according to claim 5, of particle size of 3 μm to 200 μm.
Claim 9
Dependent Claim
58 words
A process for the production of primary hydroxyl silica as claimed in claim 1, which comprises reacting an intermediate (2) ##STR10## with a suitable oxidizing agent to provide an intermediate (3) ##STR11## which is reacted with sodium borohydride (NaBH 4 ) to provide the desired compound (4), ##STR12## where m and n are as defined in claim 1.
Claim 10
Dependent Claim
34 words
A process according to claim 7, further comprising activating said compound (4) by reaction with a chloroformate or with a 1,1-carbodiimidazole, with tresylchloride, with 1,1,1-trichloro-2-monochloroethylsuccinimide carbonate, or by a sulfonylchloride or with cyanogen bromide.
Claim 11
Dependent Claim
14 words
A process according to claim 7 wherein the chloroformate is of the formula ##STR13##
Claim 12
Dependent Claim
14 words
A process according to claim 7 where the diimide is of the formula ##STR14##
References Cited (Backward Citations)
US4788909A
Cited
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-01-15 | 1993-07-17 | 1994-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-15 | 1997-07-17 | 1998-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-15 | 2001-07-17 | 2002-01-16 | $7700.00 | Window Closed / Lapsed |