The term "dPEG®" is Quanta BioDesigns trademarked acronym for "discrete poly(ethylene glycol)" or "discrete PEG". Each of our products represents a single compound with a unique, specific, single molecular weight (MW) PEG synthesized de novo from pure, small units (e.g., triethylene glycol or tetraethylene glycol). In our numbering system, we name compounds as dPEG®nn, where nn stands for the number of oxygen atoms in the spacer unit. We do this in order to simplify the naming of the compounds. Our catalog has the exact structure of the single compound. Thus, for example, product number 10244, amino-dPEG®4-acid, has an amino group on one end, four (4) ethylene oxide units, and a carboxylic acid group on the other end, as shown beside: Some people prefer the term "monodisperse" to describe these PEG compounds. While not an inappropriate term, "monodisperse" implies either that - the compounds are single compounds purified from a polymeric mixture, or
- there is only one compound formed from a polymeric process, which is purely a theoretical concept. We prefer the term "discrete", since these compounds are synthesized as single MW compounds from pure starting materials via standard organic methodology. A discrete PEG is a single compound having no other PEG homologues in it.
No. Our dPEG®s are prepared de novo from pure starting materials using standard organic chemistry techniques for synthesis and purification. The only PEG in our dPEG®s is the dPEG® described in the name. We offer an intermediate range of PEG linkers and spacers ranging in molecular weights from 200 to about 1,300 Daltons. This range has heretofore been unutilized or underutilized due primarily to the lack of commercially available material and functionality. Most people using PEGs have focused either on tiny PEGs (200 D or smaller), which they synthesize themselves or on the very large polydisperse conventional PEGs (2,000-3,400 D up to 50,000 D or higher). Quanta has been making these compounds for only the past 5 years, and we are in a l earning process, starting with the smaller units (nn = 4) and working to the higher/larger sizes (nn = 8, 12 and 24). There are a number of other advantages with our low and mid range MWs versus the conventional PEGs, as well as the conventional alkyl spacer containing crosslinkers (see discussions at Questions 4 and 5, below). Many of our customers come to us thinking that they need a large PEG in order to achieve water solubility, eliminate aggregation or obtain reduced antigenicity/immunogenicity of their target molecule. In practice, many customers find that they achieve the results they desire with our intermediate range PEGs. These smaller MWs have not been available to explore all of the options or to find an optimal substitution/modification MW. It is not necessary in many cases to give a molecule, even a large biological (e.g., an antibody), a high MW PEG, to eliminate aggregation issues. We also do not yet offer very large dPEG® compounds because of the learning curve required to develop processes for synthesizing these large molecules. Numerous chemical and physical properties come into play with the larger molecules that make synthesis of very long chain PEGs challenging. The process development for these molecules is underway, but it is incomplete. Our first foray into very large dPEG® molecules likely will come in the form of branched dPEG™s. These dPEG®>s will use shorter chains (4, 8, or 12 ethylene oxide units), but will contain 3 to 9 branches, and potentially 27, providing our customers with high molecular weight PEGs as discrete single compounds. Conventional PEGs present some serious issues and challenges when used to solve drug design problems or to optimize drug design. Foremost is the fact that conventional PEGs, being polymers, are offered as substantial mixtures and therefore come as a large range of MW compounds. The MW given is simple an average MW. These mixtures are also intractable mixtures of compounds. In addition, those underivatized base materials reproducibly available for development start at MWs above 2,000 D. This lower limit of commercial availability limits the range of applications for conventional PEGs. Further, as mentioned above, the critical issue for conventional PEGs is polydispersity. For example, a polymer of MW 2,000 conservatively contains a mixture of 30-50 compounds. Polydispersity creates numerous problems in the collection of conventional drug data, including critical pharmacokinetics. Mixtures create production and reproduction nightmares inherent in working with and chemically manipulating such mixtures, which is so vital in both therapeutic and diagnostic testing and approval. Which compound is causing the effects ... positive or negative-gamma T he advantages of implementing pharmaceutical product development and modification using a single compound become obvious. Most commercial applications of conventional PEGs have to date been directed towards using the conventional PEG as a drug carrier to increase blood circulation times, thus requiring the use of high MW compounds. This approach, though successful, has entailed much expense in dealing with the challenges of controlling a very complex mixture throughout the production and scale up of these drugs. Difficulties in finding reliable, reproducible supplies of the starting, underivatized (generally methoxy-terminated) conventional, polymeric PEGs have aggravated the problem, i.e., the reproducibility of the original polymeric process. Another significant PEG application is drug conjugation. With conventional PEGs, several problems arise. First, the range and mixture of conjugates formed is huge. Second, knowing the pharmacokinetics of such a complex mixture is intrinsically problematic. Third, the shortest average commercially available conventional PEG linker is in the range of several 100s of Angstroms, and the option of looking at potentially more optimal ranges of conjugates simply has not been available. With our dPEG® offerings of discrete MW crosslinkers, this situation is changing and will continue to improve as more and more options are available. Quanta BioDesigns dPEG® compounds eliminate the problems associated with polydispersity: a. Single compound applications can now be modified with single compound dPEG®s in order to maintain their analytical and chemical uniqueness; b. When bifunctional dPEG®s are used, the size and spatial properties are again unique and will generate a compound for testing and application that has unique properties and not a range of them; and, c. Processing and scale-up is extremely simplified when having to only purify a single compound and not a complex mixture. IntroductionWhile the aliphatic methylene chain spacers, X-(CH2)n-Y, have been useful for many years, they have serious limitations and drawbacks and have needed to be replaced for some time. Quanta BioDesign, Ltd. has introduced a wide range of crosslinkers and related products, e.g., biotinylation reagents, containing discrete polyethylene glycol (dPEG®) -based spacers. With Quantas dPEG® products, the end user now has a product that not only overcomes the drawbacks of the alkyl linkers and spacers but also provides many new options and advantages that cannot be obtained with conventional alkyl linkers and spacers. Water solubility and hydrophilicityQuantas dPEG® linkers are extremely water soluble and hydrophilic, while the alkyl linkers are neither. The water solubility and hydrophilicity of our dPEG®s opens up an unexplored range of applications. In contrast, although widely used, the opposite properties in the alkyl spacers have severely limited their actual and potential uses in biological systems. At least one company (Pierce) has commercially developed the sulfo-NHS esters, which are soluble in water, but this apparent solubility disappears once the label or crosslinker is reacted, and the inherent hydrophobic properties return, and the disadvantages become apparent. Unfortunay, the inexperienced user is fooled into thinking this apparent hydrophilicity is inherent to the reagents use; it is not. The hydrophobic characteristics of the alkyl linkers and spacers are most often manifest through increased aggregation and precipitation in the modified or crosslinked products in which they are used and incorporated. With Quantas dPEG®-containing compounds, this trend is compley reversed. The dPEG®s presence adds water solubility and hydrophilicity not in the original compound, or enhances whatever is inherent in the biological compound or drug being reacted with the dPEG® derivative. The extent depends on many variable, including the size of the dPEG® reacted. For example, the biotinylation reagents using the LC linker (amino caproic acid) compared to our biotinylation reagent containing the dPEG®4 spacer offer a startling contrast. Where the LC linker has been used, once the biological compound is biotinylated, the LC-biotin with the linker will seek hydrophobic regions in the protein and hide in them, making it less available to the streptavidin. Moreover, LC-biotin compounds have serious and very short term agglomeration and precipitation problems. Pierce generated some agglomeration data that compares the sulfo-NHS-LC-biotin (the most popular biotinylation reagent on the market) with our NHS-dPEG®4 biotin, which has the dPEG®4 spacer (the length of 2x LC). The data show that human IgG biotinylated with the sulfo-NHS-LC biotin precipitates within a couple of weeks, while human IgG biotinylated NHS-dPEG®4 biotin (PN 10200) shows no sign of agglomeration at three weeks. The results are dramatic and surprising considering the sizes. As more customers use our products, we expect to hear many similar outcomes. In addition to being water soluble, the dPEG® linkers are organic soluble and can be used in organic media when this is desirable or necessary. This is true, for example, with some of the more reactive NHS esters and the like. Application Note: Because some of our crosslinkers are viscous, we often recommend our customers initially dissolve the compound in an organic solvent. With Quantas peptide synthesis dPEG® reagents, as well as with many of the modification reagents, the application is already going into an organic medium, so this property becomes essential. ImmunogenicityQuantas dPEG®-linked compounds are essentially non-immunogenic, while alkyl linkers containing more than two or three methylene groups are highly immunogenic. This is a huge advantage for dPEG®-linked compounds and a tremendous problem for alkyl linkers. Immunogenicity creates many problems for biological compounds, many of which can be solved or improved by switching to dPEG® products. We have customers using our MAL-dPEG®x-NHS esters in place of the well known and widely used SMCC and related heterobifunctional crosslinkers with dramatic results when conjugating antigens to carriers for antibody production, and the final (WORD?????) of the antibodies produced. Our customers can now extend the antigen away from the carrier to various distances with no immunogenicity in the spacer ... none!! It will be interesting to see this generally applied. Now antibodies generated using standard carriers and our dPEG®s have the potential to be of far superior quality. Non-immunogenicity has been shown repeatedly for the polydisperse polymeric PEGs, usually of high molecular weight, where we would expect any manifestations to be amplified. This is a major reason our dPEG®s have found such extensive application. Distance/spacing and distance/spacing controlApplications incorporating conventional alkyl spacers could benefit from the ability to use longer spacers than those currently available, but serious problems develop with their inclusion. Alkyl linkers are poorly water-soluble and are immunogenic from the start. Lengthening the spacer makes the crosslinker less water-soluble (and often less soluble in organic solvents also), more hydrophobic, and more immunogenic. That is why little to no change in the structural range of commercial available crosslinkers has occurred for more than 20 years. In fact, changes that have occurred have often been to shorter, not longer, chain lengths of the methylene chain spacers. In contrast, however, dPEG® spacers are extremely water soluble, hydrophilic and non-immunogenic. These properties offer no restriction to lengthening the linkers. In addition, since we are able to make the dPEG®s, which are single compounds, of any length starting with dPEG®2, with the recent introduction of our dPEG®24 product line, the chains are now approaching 90 Angstroms (90 Å) in length (linear). Quantas customers can now select spacer chain lengths from 10 to 90 Å. Researchers developing new drugs, as well as other targeting (often diagnostic) molecules, are relying more often on modeling techniques where they can predict the optimal distances for making chemical modifications. Giving them this range of options makes Quantas dPEG®s additionally attractive and valuable. We believe this is the wave of the future for crosslinking, labeling, and chemical modification. Modification reagents Quanta BioDesign offers an expanding line of commercial products, which has no counterpart with alkyl chains as above. These are specifically designed to be chemically bonded to a drug, protein, or other biological compound with the objective of (a) increasing its water solubility and/or (b) decreasing its immunogenicity, antigenicity, or toxicity. We have several products which are methoxy-terminated over a MW range of about 300 to over 1,200 D that incorporate the NHS ester. Moreover, we are expanding that line by adding two options with the NHS-carbonate activated linkage, which offer the potential to be released (e.g., as a pro-drug). We also offer methoxy-terminated products that can bond to acids, aldehydes, and sulfhydryls. The latter are of growing interest as molecular engineers can introduce the sulfhydryl almost at will using site-directed mutagenesis, and most peptides and oligos can be sulfhydryl terminated or modified. In late 2005, we plan to introduce our first branched products for use in chemical modification. This will give researchers the options of higher molecular weight dPEG®s, as well as some unique dPEG®s not previously commercially available in any format. Note: The different physical properties of the dPEG®-containing crosslinkers and modification reagents are initially perceived to be a drawback. Many of the lower MW materials are viscous liquids that can be difficult to handle. However, we find that with a little education and the initial results, our customers adapt very rapidly and creatively. Once they become accustomed to these physical properties, they can use them to their advantage by proper use of solvents and solvent systems. SummaryFor most crosslinking and labeling applications where a spacer is desired or required, the properties of the dPEG®s outlined above should cause them to displace most applications with the aliphatic spacers. Furthermore, given the longer and multiple spacer options available for the dPEG®s, end users have new options and new extensions of applications available to them. In addition, Quantas low MW dPEG®s open up applications not available to the higher MW polydisperse PEGs offered by companies like Nektar Therapeutics (the lowest MWs are typically 2,000 or 3,400, average n about = 45 and 75, respectively). Moreover, polydisperse PEGs are complex polymer mixtures, while Quantas discrete PEGs are single compounds, giving the end-user tremendous advantages over polydisperse PEGs at all steps of the application or process. Quanta BioDesign, Ltd. is committed to developing highly cost effective, high purity, and proprietary processes for making the entire range of useful dPEG® compounds and their derivatives for application to the widest range of therapeutic, diagnostic, and molecular engineering applications. Our compounds often open doors that have never been opened before due to the absence of the proper molecular tools. These tools are now offered and are being developed by Quanta BioDesign, Ltd. Finally, we are extremely interested in getting suggestions and feedback from our customers about new options in making other valuable dPEG® products. We are located in a beautiful northern suburb of Columbus, Ohio, the home of The Ohio State University, which is one of the best public universities in the United States and the home of the world-famous Ohio State Buckeyes sports teams. A recent survey positioned Powell as the 18th nicest city in the country. Yes, and we are really in Ohio. Product# Product Name 10000 Bioconjugate Techniques 10010 Biotin-dPEG..-PFP ester 10012 MBS (m-maleimidobenzoyl NHS ester) 10014 Tris (2-carboxyethyl)phosphine Hydrochloride (TCEP) 10015 Bis-dPEG..-PFP ester 10033 Fmoc-N-amido-dPEG..-acid 10041 Amino-dPEG..-t-boc-hydrazide 10043 Fmoc-N-amido-dPEG..-t-boc-hydrazide 10044 NHS-dPEG..-t-boc-hydrazide 10053 Fmoc-N-amido-dPEG..-acid 10061 Amino-dPEG..-t-butyl ester 10063 Fmoc-N-amido-dPEG..-acid 10064 MAL-dPEG..-NHS ester 10065 MAL dPEG..-acid 10066 CBZ-N-amido-dPEG..-acid 10067 Amino-dPEG..-acid 10156 S-acetyl-dPEG..-alcohol 10160 S-acetyl-dPEG..-alcohol 10166 Methoxytrityl-S-dPEG..-acid 10170 Amino-dPEG...-alcohol 10171 t-boc-N-amido-dPEG...-alcohol 10172 t-boc-N-amido-dPEG...-amine 10174 m-dPEG..-amine 10175 m-dPEG..-amine 10177 MPS-EDA.TFA 10180 dPEG..-SATA acid (S-acetyl-dPEG..-acid) 10181 dPEG..-SATA (S-acetyl-dPEG..-NHS ester) 10182 dPEG..-SATA acid (S-acetyl-dPEG..-acid) 10183 Thiol-dPEG..-acid 10184 dPEG..-SATA (S-acetyl-dPEG..-NHS ester) 10185 Hydroxy-dPEG..-t-butyl ester 10193 Biotin-dPEG..-NH.+TFA- 10194 NHS-S-S-dPEG..-biotin 10195 Biotin-dPEG...-MAL 10196 Biotin-dPEG...-NH. 10197 dPEG...-biotin acid 10198 NHS-dPEG...-biotin 10199 dPEG..-biotin acid 10200 NHS-dPEG..-biotin 10201 Biotin-dPEG..-MAL 10202 NHS-dPEG..-biotinidase resistant biotin 10205 NHS-biotin 10210 MAL-dPEG..-t-boc-hydrazide 10211 m-dPEG..-NHS ester 10213 Fmoc-N-amido-dPEG..-acid 10214 MAL-dPEG..-NHS ester 10215 Bis-MAL-dPEG.. 10217 MPS (NHS-3-maleimidopropionate) 10218 Biotin-dPEG..-cyanocobalamin 10219 Biotin-dPEG..-hydrazide 10220 t-boc-N-amido-dPEG..-acid 10221 Amino-dPEG..-t-butyl ester 10223 Hydroxy-dPEG..-t-butyl ester 10224 Bis-dPEG..-NHS ester 10225 t-boc-N-amido-dPEG..-amine 10226 t-boc-N-EDA 10229 Lissamine Rhodamine B sulfonamide-dPEG..-acid 10230 Bis-dPEG..-acid 10231 Bromoacetamido-N’-t-boc-amido-dPEG..-diamine 10232 Bis-Maleimide amine,TFA salt 10233 O-benzyl-dPEG..-acid 10234 m-dPEG..-acid 10236 Bis-dPEG..-acid 10237 Bis-dPEG.., half benzyl half NHS ester 10240 Amino-dPEG..-alcohol 10243 Fmoc-N-amido-dPEG..-acid 10244 Amino-dPEG..-acid 10245 Bis-dPEG..-acid 10246 Bis-dPEG..-NHS ester 10247 Thiol-dPEG..-acid 10249 Amino-dPEG..-alcohol 10250 t-boc-N-amido-dPEG..-alcohol 10251 m-dPEG..-alcohol 10252 m-dPEG...-alcohol 10254 m-dPEG..-tosylate 10256 m-dPEG..-tosylate 10259 m-dPEG..-tosylate 10260 m-dPEG..-NHS ester 10261 dPEG...-diol 10262 m-dPEG...-NHS ester 10264 Amino-dPEG..-t-butyl ester 10265 MAL-dPEG..-acid 10266 MAL-dPEG..-NHS ester 10267 Biotin-dPEG..-benzophenone 10268 CBZ-N-amido-dPEG..-acid 10269 CBZ-N-amido-dPEG..-amine 10271 Amino-dPEG..-t-butyl ester 10273 Fmoc-N-amido-dPEG..-acid 10274 MAL-dPEG..-NHS ester 10275 MAL-dPEG..-acid 10276 CBZ-N-amido-dPEG..-acid 10277 Amino-dPEG..-acid 10278 m-dPEG..-amine 10281 Amino-dPEG...-t-butyl ester 10283 Fmoc-N-amido-dPEG...-acid 10284 MAL-dPEG...-NHS ester 10285 MAL-dPEG...-acid 10286 CBZ-N-amido-dPEG...-acid 10287 Amino-dPEG...-acid 10288 m-dPEG...-amine 10289 m-dPEG...-MAL 10291 Amino-dPEG...-t-butyl ester 10292 t-boc-N-amido-dPEG...-acid 10293 Fmoc-N-amido-dPEG...-acid 10294 MAL-dPEG...-NHS ester 10295 MAL-dPEG...-acid 10296 CBZ-N-amido-dPEG...-acid 10297 Amino-dPEG...-acid 10298 m-dPEG...-amine 10300 Trityl-S-dPEG..-acid 10301 Methoxytrityl-S-dPEG..-acid 10304 m-dPEG...-NHS ester 10305 m-dPEG..-NHS carbonate 10307 m-dPEG...-NHS carbonate 10308 Biotin-dPEG..-TFPA 10311 Amino-dPEG...-t-butyl ester 10313 Fmoc-N-amido-dPEG...-acid 10314 MAL-dPEG...-NHS ester 10315 MAL-dPEG...-acid 10316 CBZ-N-amido-dPEG...-acid 10317 Amino-dPEG...-acid 10318 m-dPEG...-amine 10319 m-dPEG...-MAL 10320 Bis-dPEG...-acid 10322 m-dPEG...-NHS ester 10323 MPS-Acid 10324 m-dPEG..-acid 10325 Bis-dPEG..-biotin 10326 m-dPEG..-acid 10327 m-dPEG..-NHS ester 10328 m-dPEG...-acid 10330 Amino-dPEG..-methyl ester KIT 10331 Amino-dPEG..-methyl ester KIT 10332 Amino-dPEG..-methyl ester KIT 10334 Amino-dPEG...-methyl ester KIT 10335 Amino-dPEG...-methyl ester KIT 10336 Amino-dPEG...-methyl ester KIT 10337 Amino-dPEG...-methyl ester KIT 10338 MAL-dPEG..-acid 10339 m-dPEG...-acid 10340 Azido-dPEG...-alcohol 10342 Amino-dPEG...-ODMT 10344 Biotin-dPEG....-azide 10346 DNP-dPEG..-acid 10347 DNP-dPEG..-NHS ester 10348 m-dPEG..-alcohol 10355 Biotinoylsarcosine 10356 Biotinoyl-2-Aminobutyric acid 10358 Methoxytrityl-N-dPEG..-acid 10360 NHS-dPEG..-Lys-(dPEG..-biotin). 10361 Diamido-dPEG...-diamine 10362 m-dPEG..-Propionaldehyde 10363 m-dPEG..-Propionaldehyde 10364 m-dPEG...-Propionaldehyde 10365 MBS-dPEG..-acid 10366 MBS-dPEG..-NHS ester 10367 MBS-dPEG..-acid 10368 MBS-dPEG..-NHS ester 10369 MBS-dPEG...-acid 10370 MBS-dPEG...-NHS ester 10371 MBS-dPEG...-acid 10372 MBS-dPEG...-NHS ester 10373 SPDP-dPEG..-acid 10374 SPDP-dPEG..-NHS ester 10375 SPDP-dPEG..-acid 10376 SPDP-dPEG..-NHS ester 10377 SPDP-dPEG...-acid 10378 SPDP-dPEG...-NHS ester 10379 SPDP-dPEG...-NHS ester 10380 SPDP-dPEG...-acid 10393 Methoxytrityl-N-dPEG..-acid 10394 Methoxytrityl-N-dPEG...-acid 10395 Methoxytrityl-N-dPEG...-acid 10396 Methoxytrityl-N-dPEG...-acid 10397 Bis-MAL-dPEG... 10398 DNP-dPEG...-acid 10399 DNP-dPEG...-NHS ester 10400 Amino-dPEG..-(m-dPEG...). 10401 NHS-dPEG..-( m-dPEG...).-ester 10402 Carboxyl-dPEG..-(m-dPEG...). 10406 MAL-dPEG..-(m-dPEG...). 10410 Amino-dPEG..-(m-dPEG..) . 10411 NHS-dPEG..-( m-dPEG..).-ester 10412 Carboxyl-dPEG..-(m-dPEG..). 10416 MAL-dPEG..-(m-dPEG..). 10420 Amino-dPEG..-(m-dPEG..). 10421 NHS-dPEG..-( m-dPEG..).-ester 10422 Carboxyl-dPEG..-(m-dPEG..). 10424 m-dPEG...-Propionaldehyde 10426 MAL-dPEG..-(m-dPEG..). 10453 Amino-dPEG..-(m-dPEG...). 10454 NHS-dPEG..-( m-dPEG...).-ester 10455 Carboxyl-dPEG..-(m-dPEG...). 10456 MAL-dPEG..-(m-dPEG...). 10501 Azido-dPEG..-NHS ester g 10502 Azido-dPEG..-acid 10503 Azido-dPEG..-NHS ester 10505 Azido-dPEG...-NHS ester 10510 Propargyl amine 10511 Propargyl-dPEG..-NHS ester 10512 Azido-dPEG..-acid 10513 Azido-dPEG...-acid 10514 Azido-dPEG...-acid 10522 Azido-dPEG..-amine 10523 Azido-dPEG..-amine 10524 Azido-dPEG...-amine 10525 Azido-dPEG...-amine 10526 Azido-dPEG...-amine 10531 m-dPEG...-Azide (Azido-m-dPEG...) 10532 m-dPEG..-Azide (Azido-m-dPEG..) 10534 m-dPEG..-Azide (Azido-m-dPEG..) 10536 m-dPEG...-Azide (Azido-m-dPEG...) 10540 m-dPEG...-Azide (Azido-m-dPEG...) 10541 Azido-dPEG..-alcohol 10542 Azido-dPEG..-alcohol 10543 Azido-dPEG...-alcohol 10544 Azido-dPEG...-alcohol 10602 Fmoc-N-amido-(dPEG..-biotin) acid 10613 Fmoc-N-Lys-(dPEG..-biotin)-OH-(acid) 10615 Fmoc-N-Lys-(dPEG...-biotin)-OH-(acid) 10697 Bis-dPEG..-PFP ester 10698 Bis-dPEG..-acid 10699 Bis-dPEG..-NHS ester 10717 Hydroxy-dPEG..-t-butyl ester 10719 Hydroxy-dPEG...-t-butyl ester 10720 Hydroxy-dPEG...-t-butyl ester 10721 Hydroxy-dPEG...-t-butyl ester 10722 Hydroxy-dPEG...-t-butyl ester 10723 Bis-dPEG..-acid 10724 Bis-dPEG..-NHS ester 10725 Bis-dPEG..-acid 10726 Bis-dPEG..-NHS ester 10728 m-dPEG...-alcohol 10733 m-dPEG...-acid 10745 m-dPEG..-MAL 10746 m-dPEG..-MAL 10751 Methoxytrityl-N-dPEG..-TFP ester 10752 Methoxytrityl-N-dPEG..-TFP ester 10753 Methoxytrityl-N-dPEG...-TFP ester 10754 Methoxytrityl-N-dPEG...-TFP ester 10755 Methoxytrityl-N-dPEG...-TFP ester 10760 t-boc-N-amido-dPEG..-acid 10761 t-boc-N-amido-dPEG...-acid 10763 t-boc-N-amido-dPEG...-acid 10773 dPEG...-biotin acid 10774 NHS-dPEG...-biotin 10776 dPEG...-biotin acid 10780 Biotin-dPEG...-azide 10784 Biotin-dPEG...-azide 10785 Biotin-dPEG...-MAL 10786 Biotin-dPEG...-NH. 10787 Biotin-dPEG...-azide 10792 m-dPEG..-thiol 10793 m-dPEG..-thiol 10794 m-dPEG...-thiol 10799 m-dPEG..-Lipoic acid 10800 m-dPEG..-Lipoic acid 10801 m-dPEG...-Lipoic acid 10804 m-dPEG...-Lipoic acid 10806 Lipoimide-dPEG..-acid 10807 Lipoimide-dPEG..-acid 10808 Lipoimide-dPEG...-acid 10809 Lipoimide-dPEG...-acid 10811 Lipoimide-dPEG...-acid 10817 MAL-dPEG..-Lipoic acid 10819 MAL-dPEG...-Lipoic acid 10820 Biotin-dPEG..-Lipoic acid 10822 Biotin-dPEG...-Lipoic acid 10825 Biotin-dPEG..-azide 10826 Biotin-dPEG..-NH. 10843 Methoxytrityl-N-dPEG...-TFP ester 10845 Methoxytrityl-N-dPEG...-TFP ester 10846 Methoxytrityl-S-dPEG...-acid 10847 Methoxytrityl-S-dPEG...-acid 10848 Methoxytrityl-N-dPEG...-acid 10850 Thiol-dPEG...-acid 10851 dPEG...-SATA acid (S-acetyl-dPEG...-acid) 10852 dPEG...-SATA (S-acetyl-dPEG...-NHS ester) 10853 Thiol-dPEG...-acid 10854 dPEG...-SATA acid (S-acetyl-dPEG...-acid) 10855 dPEG...-SATA (S-acetyl-dPEG...-NHS ester) 10856 SPDP-dPEG...-acid 10857 SPDP-dPEG...-NHS ester 10858 Thiol-dPEG...-acid 10859 dPEG...-SATA acid (S-acetyl-dPEG...-acid) 10860 dPEG...-SATA (S-acetyl-dPEG...-NHS ester) 10861 SPDP-dPEG...-acid 10862 SPDP-dPEG...-NHS ester 10866 SPDP-dPEG...-acid 10867 SPDP-dPEG...-NHS ester 10868 Amino-dPEG...-alcohol 10869 Amino-dPEG...-alcohol 10894 m-dPEG...-alcohol 10895 m-dPEG...-alcohol 10898 m-dPEG...-NHS carbonate 10899 m-dPEG...-NHS carbonate 10901 Amino-dPEG...-t-butyl ester 10902 t-boc-N-amido-dPEG...-acid 10903 Fmoc-N-amido-dPEG...-acid 10906 CBZ-N-amido-dPEG...-acid 10907 Amino-dPEG...-acid 10908 m-dPEG...-amine 10909 m-dPEG...-acid 10910 m-dPEG...-NHS ester 10918 m-dPEG...-amine 10920 m-dPEG...-NHS ester 10921 Amino-dPEG...-t-butyl ester 10922 t-boc-N-amido-dPEG...-acid 10923 Fmoc-N-amido-dPEG...-acid 10924 MAL-dPEG...-NHS ester 10925 MAL-dPEG...-acid 10926 CBZ-N-amido-dPEG...-acid 10927 Amino-dPEG...-acid 10928 m-dPEG...-acid 10929 m-dPEG..-NHS carbonate 10930 m-dPEG...-NHS carbonate 10931 m-dPEG...-MAL 10932 m-dPEG...-MAL 10939 S-acetyl-dPEG...-alcohol 10940 S-acetyl-dPEG...-alcohol 10941 S-acetyl-dPEG...-alcohol 10942 m-dPEG...-alcohol 10953 Bis-dPEG...-acid 10954 Bis-dPEG...-NHS ester 10955 Bis-dPEG...-acid 10956 Bis-dPEG...-NHS ester 10957 Amino-dPEG..-t-boc-hydrazide 10958 Amino-dPEG...-t-boc-hydrazide 10961 MAL-dPEG..-t-boc-hydrazide 10962 MAL-dPEG...-t-boc-hydrazide 10967 Bis-dPEG...-acid 10968 Bis-dPEG...-NHS ester 10978 Bis-dPEG...-acid 10979 Bis-dPEG...-NHS ester 10980 Bis-dPEG...-PFP ester 10981 Bis-dPEG..-PFP ester 10982 Bis-dPEG..-PFP ester 10983 Bis-dPEG..-PFP ester 10984 Bis-dPEG...-PFP ester 10985 Bis-dPEG...-PFP ester 10986 Bis-dPEG...-PFP ester 10987 Bis-dPEG..-PFP ester 10988 Bis-dPEG..-NHS ester 10994 Fmoc-N-amido-dPEG..-NHS ester 10995 Fmoc-N-amido-dPEG..-NHS ester 10996 Fmoc-N-amido-dPEG...-NHS ester |