50-35-1 Usage
Uses
Used in Pharmaceutical Industry:
Thalidomide is used as a sedative and has certain efficacy in treating various types of leprosy reactions such as fever, erythema nodosum, neuralgia, joint pain, and swollen lymph nodes. It is also used as an immunomodulatory agent, primarily in combination with dexamethasone, to treat multiple myeloma.
Used in Oncology:
Thalidomide is used as an anticancer agent, particularly in the treatment of multiple myeloma and erythema nodosum leprosum (ENL) in non-pregnant individuals. It has been shown to inhibit FGF-induced angiogenesis, replication of human immunodeficiency virus type 1 (HIV-1), and induce apoptosis in primary human embryonic fibroblasts.
Used in Anti-inflammatory Applications:
Thalidomide has been proven effective in treating inflammation associated with diseases such as leprosy, arthritis, and Crohn’s disease.
Used in Prenatal Care (Historically):
Thalidomide was prescribed as an anti-nausea agent to help pregnant women with morning sickness in the late 1950s. However, it was found to be a potent teratogen, causing many different forms of birth defects, and was subsequently withdrawn from the market.
Used in Research:
Thalidomide and its synthetic analogs have been studied for their potential effectiveness against cancer and other diseases, with recent research focusing on their interactions with the protein cereblon (CRBN), a ubiquitously-expressed E3 ligase, which accounts for the immunomodulatory and antiproliferative effects of these compounds.
Glutamic acid derivatives
Thalidomide is a kind of synthetic glutamic acid derivatives. At room temperature, it is a kind of white crystalline powder, and is odorless, tasteless, and slightly soluble in water, methanol, ethanol or acetone, highly soluble in dimethylformamide or pyridine, but insoluble in ether, chloroform or benzene.
At 1950s, Germany developed the drug mainly for treating epilepsy. However, due to the lack of efficacy, then it is further used as an adjunct for sleeping while also widely used as antiemetic drug for pregnant women during their pregnancy.
At early 1960s, thalidomide incident---there had been a lot of reports about birth defect caused by thalidomide (such as: short limb malformations, bone defect, ear missing, cleft lip, heart and gastrointestinal tract abnormalities, etc.). Thereby, it was further prohibited by many countries, and subjected to withdrawal from the pharmaceutical market; but scientists did not totally negate thalidomide and continued to carry out in-depth research; there has been much encouraging and promising progress on the pharmacologic mechanisms of immunity, anti-inflammatory, and anti-angiogenic as well as the clinical treatment of various kinds of difficult disease, making people gain new understanding of the functions of thalidomide.
Since the 1970s, with the emergence of the various research progresses of leprosy, rheumatism and various types of cancer, Israel dermatologists had applied thalidomide as a sedative for patients of erythema nodosum leprosy and obtain rapid alleviation of symptoms. After that many patients of erythema nodosum leprosy had received good therapeutic effects. In1998, the FDA approved thalidomide for the treatment of erythema nodosum leprosy.
In 2004, during the American Society of Hematology annual meeting, RaJkumar from the US Mayo Clinic reported the progress of two studies about using thalidomide and its analogs (lenalidomide) in first-line treatment of multiple myeloma. Both thalidomide and its analogs, lenalidomide are effective in the treatment of multiple myeloma with lenalidomide having a better effect than thalidomide.
In May 2006, the US FDA approved it for the treatment of multiple myeloma.
The above information is edited by the lookchem of Dai Xiongfeng.
Treatment of rheumatism
Foreign scholars have reported that when using thalidomide for treatment of 7 rheumatoid patients who can’t be cured by various kinds of anti-inflammatory drugs and immune inhibition, the symptoms were alleviated in most cases within a few weeks at the dose in 400~600mg/d. All patients have their erythrocyte sedimentation rate and rheumatoid factor titers either be normalized or be decreased, wherein 1 case of rheumatoid nodules disappeared at 12 weeks. Someone have ever combined thalidomide with methotrexate for treating 7 cases of refractory rheumatoid arthritis, wherein in 5 cases of patient who persists in treatment, 4 cases obtained alleviated joints tenderness and reduced joints swelling feeling within 3 to 9 months.
Thalidomide to treat rheumatism diseases as follows:
1. Behcet's disease.
2. Systemic lupus erythematosus.
3. Rheumatoid arthritis.
4. Erythema nodosum, Crohn's disease.
5. Scleroderma: at 12 weeks after the start of treatment, it can significantly alleviate the symptoms of gastroesophageal reflux, heal duodenal ulcer and lead to hypopigmentation.
6. Adult Still's disease.
7. Refractory ankylosing spondylitis, multiple myeloma (MM).
Clinical treatment of rheumatism should start from small dose at 25--50mg/day per night, gradually increase the amount to 100--200mg/day with the maximum not exceeding 400mg/day.
Side effects
Adverse reactions during the treatment using thalidomide include: drowsiness, dizziness, drowsiness, headache, constipation, nausea, vomiting, dry mouth, dry skin, erythema and papules and vesicular transient rash; but they usually are not serious and can disappear after termination of administration.
The adverse reactions that should be noted is multiple neuritis with the main symptom being a surface or deep sensory loss and muscle weakness; the occurrence of symptoms is not proportional to the dose and duration; the time when the symptoms began to appear also varies greatly; for the cases without treatment termination, such symptoms are irreversible. In addition, leukopenia, abnormal liver function as well as the well-known teratogenic effects also should be taken care. Other rare side effects include bradycardia, edema, abnormal blood clotting, kidney failure, pneumonia, paresthesia, and hypothyroidism.
Side effects
Thalidomide is a highly teratogenic drug, characteristically
causing phocomelia (aplasia of the midportions of
the limbs). Even a single dose may cause fetal malformation.
Thalidomide should be prescribed to women of
childbearing potential only when no acceptable alternative
exists. Because it is not known whether thalidomide
is present in the ejaculate of males receiving the drug,
male patients must use a latex condom when engaging in
sexual activity with women of childbearing potential.Other side effects of thalidomide may include sedation
(in fact, thalidomide was originally marketed in
Europe as a sleeping aid), constipation, and peripheral
neuropathy, which may be permanent.
Originator
Contergan,Grunenthal,Germany
Indications
Thalidomide (Thalomid) is a derivative of glutamic acid
that is chemically related to glutethimide. It exerts a
number of biological effects as an immunosuppressive,
antiinflammatory, and antiangiogenic agent, yet its
mechanisms of action have not been fully elucidated.
Thalidomide potently inhibits production of tumor
necrosis factor (TNF) and interleukin (IL) 12, and its
effect on these and other cytokines may account for
some of its clinical effects.
Manufacturing Process
26 g of N-phthalyl glutaminic acid anhydride are melted with 12 g of urea in
an oil bath at 170-180°C until the reaction is completed, which takes about 20
min. The reaction takes place with violent evolution of carbon dioxide and
ammonia. After cooling, the reaction product is recrystallised by fractionation
from 95% alcohol, and the first fraction may contain phthalic acid derivatives.
The required product N-(2,6-dioxo-3-piperidyl)-phthalimide melts at 269-
271°C. The yield is about 65-70% of the theoretical.
Therapeutic Function
Sedative, Hypnotic, Antiarthritic
World Health Organization (WHO)
Notwithstanding the highly potent teratogenic action of
thalidomide, this drug retains a place in the treatment of reactional lepromatous
leprosy and several serious dermatological conditions refractory to other
treatment. In many countries, the competent authorities have granted exemption
from licensing requirements to enable doctors to obtain limited supplies of
thalidomide under strictly controlled circumstances for use in named patients.
Arrangements have also been made by some national drug regulatory authorities
for thalidomide to be used in institutions concerned with the treatment of leprosy.
Synthesis Reference(s)
Synthetic Communications, 33, p. 1375, 2003 DOI: 10.1081/SCC-120018698
Air & Water Reactions
Insoluble in water.
Reactivity Profile
Organic amides/imides, such as Thalidomide, react with azo and diazo compounds to generate toxic gases. Flammable gases are formed by the reaction of organic amides/imides with strong reducing agents. Amides are very weak bases (weaker than water). Imides are less basic yet and in fact react with strong bases to form salts. That is, they can react as acids. Mixing amides with dehydrating agents such as P2O5 or SOCl2 generates the corresponding nitrile. The combustion of these compounds generates mixed oxides of nitrogen (NOx).
Health Hazard
Thalidomide is a strong teratogen. Exposureto Thalidomide during the first trimesterof pregnancy resulted in deformities inbabies. Infants born suffered from ameliaor phocomelia, the absence or severe shortening of limbs. Administration of thalidomide in experimental animals caused fetaldeaths, postimplantation mortality, and specific developmental abnormalities in theeyes, ear, central nervous system, musculoskeletal system, and cardiovascular system. Several thousand children were affected.The drug has been withdrawn from themarket.Thalidomide is usually administeredorally. Its toxicity is dose dependent. Someother effects are drowsiness, constipation andrash and nerve damage in the arms and legs.Interest in thalidomide resurged in recentyears because of its antitumor activity in thetreatment of multiple myeloma (Oxberry andJohnson 2006). The compound is an inhibitorof angiogenesis, that is, it prevents formationof new blood vessels in tumors. Also, it hasbeen found to be effective in treating AIDS-related Kaposis sarcoma.
Fire Hazard
Flash point data for Thalidomide are not available; however, Thalidomide is probably combustible.
Biological Activity
Teratogen, sedative-hypnotic with inherent anti-inflammatory properties. A selective inhibitor of tumor necrosis factor α (TNF- α ) synthesis.
Biochem/physiol Actions
(±)-Thalidomide selectively inhibits biosynthesis of tumor necrosis factor α (TNF-α). It also functions as an inhibitor of angiogenesis, an immunosuppressive agent, a sedative and a teratogen. Furthermore, thalidomide is known to exhibit antitumor functions in refractory multiple myeloma.
Mechanism of action
Its absorption from the gastrointestinal tract is slow,
with peak plasma levels being reached after 3 to 6
hours. It appears to undergo nonenzymatic hydrolysis in
the plasma to a large number of metabolites.The elimination
half-life is approximately 9 hours.
Clinical Use
Thalidomide is approved for use in the United
States for the treatment of cutaneous manifestations
of erythema nodosum leprosum, a potentially lifethreatening
systemic vasculitis that occurs in some patients
with leprosy.Although not approved for other indications,
thalidomide has also been shown to be very
effective in the management of Beh?et’s disease, HIVrelated
mucosal ulceration (aphthosis), and select cases
of lupus erythematosus.
Safety Profile
Poison by ingestion. Moderately toxic by skin contact and intraperitoneal routes. Human teratogenic effects by ingestion: developmental abnormalities of the musculoskeletal and cardiovascular systems. Experimental reproductive effects. Questionable carcinogen with experimental tumorigenic and teratogenic data. Human mutation data reported. It was commonly used as a prescription drug in Europe in the late 1950s and early 1960s. Its use was dscontinued because it was lscovered to cause serious congenital abnormalities in the fetus, notably amelia and phocomelia (absence or deformity of the limbs, including hands and feet) when taken by a woman during early pregnancy. When heated to decomposition it emits toxic fumes of NOx. Used as a sedative and hypnotic.
Drug interactions
Potentially hazardous interactions with other drugs
Thalidomide enhances the effects of barbiturates,
alcohol, chlorpromazine and reserpine.
Use with caution with other drugs that can cause
peripheral neuropathy.
Metabolism
Thalidomide is metabolised almost exclusively by nonenzymatic hydrolysis. In plasma, unchanged thalidomide
represents 80% of the circulatory components.
Unchanged thalidomide was a minor component
(<3% of the dose) in urine. In addition to thalidomide,
hydrolytic products N-(o-carboxybenzoyl) glutarimide
and phthaloyl isoglutamine formed via non-enzymatic
processes are also present in plasma and in urine.
Toxicity evaluation
The mechanism of teratogenecity of the thalidomide is not
clearly understood; however, recent studies have shed some light
on the potential mechanism. CRBN has been identified as
a thalidomide-binding protein. The teratogenic effects start with
binding of thalidomide to CRBN and inhibiting the associated
ubiquitin ligase activity.Many E3 ubiquitin ligases are important
for various physiological processes such as cell cycle regulation,
carcinogenesis, immune response, and development. It has been
shown that CRBN forms an E3 ubiquitin ligase complex with
damaged DNA binding protein 1 (DDB1) and Cullin-4A
(Cul4A), which are important factors for expression of the
fibroblast growth factor Fgf8 in zebra fish and chicks as well as
the limb outgrowth. In thalidomide-treated zebra fish embryos,
formation of proximal endoskeletal disc of the pectoral fin was
severely inhibited and the otic vesicle size was significantly
reduced. Pectoral fins and otic vesicles in fish share common
molecular pathways with tetrapod limbs and ears development.
Down-regulation of the CRBN complex causes similar developmental
defects in zebra fish. Thalidomide does not cause limb
malformations in rodents but does in rabbits, monkeys. In
pregnant rats, thalidomide can cause other types of developmental
defects such as vertebral column, rib, and eye malformation.
There is very strong conservation of the amino acid
sequence of CRBN between rat, rabbit, monkey, mouse and
human and has been shown that they can bind to thalidomide.
The role and importance of CRBN in different species have not
been identified; therefore, the degree of teratogenecity could
depend in part on the nature of the protein substrates that are
modified by CRBN activity during embryonic development.
There are some species differences in teratogenecity between
thalidomide and its close analogs.
References
1) Ito et al. (2010), Identification of a primary target of thalidomide teratogenicity; Science, 327 1345
2) Weglicki et al. (1993), Inhibition of tumor necrosis factor-alpha by thalidomide in magnesium deficiency; Mol. Cell. Biochem., 129 195
3) D’Amato et al. (1994), Thalidomide is an inhibitor of angiogenesis ; Proc. Natl. Acad. Sci. USA, 91 4082
Check Digit Verification of cas no
The CAS Registry Mumber 50-35-1 includes 5 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 2 digits, 5 and 0 respectively; the second part has 2 digits, 3 and 5 respectively.
Calculate Digit Verification of CAS Registry Number 50-35:
(4*5)+(3*0)+(2*3)+(1*5)=31
31 % 10 = 1
So 50-35-1 is a valid CAS Registry Number.
InChI:InChI=1/C13H10N2O4/c16-10-6-5-9(11(17)14-10)15-12(18)7-3-1-2-4-8(7)13(15)19/h1-4,9H,5-6H2,(H,14,16,17)
50-35-1Relevant articles and documents
A Metal-Organic Framework (MOF)-Based Multifunctional Cargo Vehicle for Reactive-Gas Delivery and Catalysis
Chen, Donna A.,Corkill, Ryan E.,Garashchuk, Sophya,Jayaweera, H. D. A. Chathumal,Karakalos, Stavros G.,Kittikhunnatham, Preecha,Lauterbach, Jochen,Leith, Gabrielle A.,Martin, Corey R.,Mathur, Abhijai,McCullough, Katherine,Naglic, Jennifer K.,Park, Kyoung Chul,Shustova, Natalia B.,Smith, Mark D.
, (2022/02/01)
The efficient delivery of reactive and toxic gaseous reagents to organic reactions was studied using metal-organic frameworks (MOFs). The simultaneous cargo vehicle and catalytic capabilities of several MOFs were probed for the first time using the examples of aromatization, aminocarbonylation, and carbonylative Suzuki–Miyaura coupling reactions. These reactions highlight that MOFs can serve a dual role as a gas cargo vehicle and a catalyst, leading to product formation with yields similar to reactions employing pure gases. Furthermore, the MOFs can be recycled without sacrificing product yield, while simultaneously maintaining crystallinity. The reported findings were supported crystallographically and spectroscopically (e.g., diffuse reflectance infrared Fourier transform spectroscopy), foreshadowing a pathway for the development of multifunctional MOF-based reagent-catalyst cargo vessels for reactive gas reagents as an attractive alternative to the use of toxic pure gases or gas generators.
Discovery of triazolyl thalidomide derivatives as anti-fibrosis agents
Tang, Kai-Wei,Hsu, Wen-Li,Chen, Cheng-Ru,Tsai, Ming-Hsien,Yen, Chia-Jung,Tseng, Chih-Hua
, p. 3589 - 3599 (2021/03/03)
Fibrosis with excessive accumulation of extracellular matrix (ECM) often causes progressive organ dysfunction and results in many inflammatory and metabolic diseases, including systemic sclerosis, pulmonary fibrosis, advanced liver disease and advanced kidney disease. The store-operated calcium entry (SOCE) pathway and the related signaling pathway were both found to be the important routes for fibrogenesis. Our aim in this study was to discover novel compounds to inhibit fibrogenesis. A number of triazolyl thalidomide derivatives were synthesized and evaluated for their anti-fibrosis activities. Compounds 7b-e, 8c-d, 10a-b and 10e inhibited intracellular Ca2+ activation and showed no cytotoxicity. Among them, 6-{4-[(3-(1,3-dioxoisoindolin-2-yl)-2,6-dioxopiperidin-1-yl)methyl]-1H-1,2,3-triazol-1-yl}hexanoic acid (10e) with the most potent inhibitory effect was chosen for further examination. The results revealed that compound 10e, a SOCE inhibitor, reversed the migratory ability of TGF-β1-induced myofibroblasts, dedifferentiated myofibroblasts to fibroblasts due to cytoskeleton remodeling, and restrained myofibroblast activation by targeting Orai1 and TGF-β1/SMAD2/3 signaling pathways. The in silico study indicated that compound 10e, with the appropriate lipophilic carbon chain and carboxylic acid, showed a good drug-likeness model score. Conclusively, the SOCE inhibitor, compound 10e, is used as a promising lead compound for the development of a new treatment for fibrosis. This journal is
IMIDE-BASED MODULATORS OF PROTEOLYSIS AND METHODS OF USE
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Page/Page column 224; 225, (2019/08/12)
The description relates to imide-based compounds, including bifunctional compounds comprising the same, which find utility as modulators of targeted ubiquitination, especially inhibitors of a variety of polypeptides and other proteins which are degraded and/or otherwise inhibited by bifunctional compounds according to the present invention. In particular, the description provides compounds, which contain on one end a ligand which binds to the cereblon E3 ubiquitin ligase and on the other end a moiety which binds a target protein such that the target protein is placed in proximity to the ubiquitin ligase to effect degradation (and inhibition) of that protein. Compounds can be synthesized that exhibit a broad range of pharmacological activities consistent with the degradation/inhibition of targeted polypeptides of nearly any type.
Facile Synthesis of Thalidomide
Vu, Binh Duong,Ho Ba, Ngoc Minh,Phan, Dinh Chau
supporting information, p. 1374 - 1377 (2019/08/12)
We report a simple and facile procedure for the preparation of thalidomide in two steps with a high overall yield (56%). The preparation was composed of a reaction between anhydride phthalic and l-glutamic acid to form N-phthaloyl-dl-glutamic acid (IV), and a cyclization step using IV reacted with ammonium acetate in diphenyl ether to create thalidomide. Reaction parameters reaction time, temperature, solvent, and molar ratio of reagents in the procedure are optimized so that the reaction performance is highest while ensuring environmental friendliness. Moreover, this process has great potential for the industrial scale of thalidomide. These compounds were identified through IR, MS, 1H NMR, and 13C NMR.
Synthesis method of thalidomide
-
Paragraph 0078-0091, (2019/08/01)
The invention relates to an industrial synthesis method of thalidomide, and specifically discloses a method, which comprises: directly synthesizing a crude product thalidomide by using phthalic anhydride and L-glutamic acid as raw materials through a two-step reaction one-pot method, and then carrying out refining purifying to obtain a finished product. According to the present invention, thalidomide is synthesized by using the two-step reaction one-pot method, microwave heating and other special equipment are not required, and the synthesis of the thalidomide anhydride intermediate is not required, such that the intermediate reaction process is eliminated, the use of acetic anhydride is avoided, the operation is simplified, the labor intensity is reduced, the production efficiency is improved, the environmental protection is achieved, and the method has high economic and social value.
Efficient Synthesis of Immunomodulatory Drug Analogues Enables Exploration of Structure–Degradation Relationships
Burslem, George M.,Ottis, Philipp,Jaime-Figueroa, Saul,Morgan, Alicia,Cromm, Philipp M.,Toure, Momar,Crews, Craig M.
, p. 1508 - 1512 (2018/07/31)
The immunomodulatory drugs (IMiDs) thalidomide, pomalidomide, and lenalidomide have been approved for the treatment of multiple myeloma for many years. Recently, their use as E3 ligase recruiting elements for small-molecule-induced protein degradation has led to a resurgence in interest in IMiD synthesis and functionalization. Traditional IMiD synthesis follows a stepwise route with multiple purification steps. Herein we describe a novel one-pot synthesis without purification that provides rapid access to a multitude of IMiD analogues. Binding studies with the IMiD target protein cereblon (CRBN) reveals a narrow structure–activity relationship with only a few compounds showing sub-micromolar binding affinity in the range of pomalidomide and lenalidomide. However, anti-proliferative activity as well as Aiolos degradation could be identified for two IMiD analogues. This study provides useful insight into the structure–degradation relationships for molecules of this type as well as a rapid and robust method for IMiD synthesis.
Homo-PROTACs for the Chemical Knockdown of Cereblon
Steinebach, Christian,Lindner, Stefanie,Udeshi, Namrata D.,Mani, Deepak C.,Kehm, Hannes,K?pff, Simon,Carr, Steven A.,Gütschow, Michael,Kr?nke, Jan
, p. 2771 - 2782 (2018/09/25)
The immunomodulatory drugs (IMiDs) thalidomide, lenalidomide, and pomalidomide, all approved for the treatment of multiple myeloma, induce targeted ubiquitination and degradation of Ikaros (IKZF1) and Aiolos (IKZF3) via the cereblon (CRBN) E3 ubiquitin ligase. IMiD-based proteolysis-targeting chimeras (PROTACs) can efficiently recruit CRBN to a protein of interest, leading to its ubiquitination and proteasomal degradation. By linking two pomalidomide molecules, we designed homobifunctional, so-called homo-PROTACs and investigated their ability to induce self-directed ubiquitination and degradation. The homodimerized compound 15a was characterized as a highly potent and efficient CRBN degrader with only minimal effects on IKZF1 and IKZF3. The cellular selectivity of 15a for CRBN degradation was confirmed at the proteome level by quantitative mass spectrometry. Inactivation by compound 15a did not affect proliferation of different cell lines, prevented pomalidomide-induced degradation of IKZF1 and IKZF3, and antagonized the effects of pomalidomide on multiple myeloma cells. Homobifunctional CRBN degraders will be useful tools for future biomedical investigations of CRBN-related signaling and may help to further elucidate the molecular mechanism of thalidomide analogues.
Synthesis and biological evaluation of thalidomide derivatives as potential anti-psoriasis agents
Tang, Kai-Wei,Tseng, Chih-Hua,Lin, Zih-Chan,Fang, Jia-You,Chen, Yeh-Long,Tzeng, Cherng-Chyi
, (2018/12/02)
Several thalidomide derivatives were synthesized and evaluated for their anti-inflammatory activity. Introduction of the benzyl group to the parent thalidomide is unfavorable in which 2-(1-benzyl-2,6-dioxopiperidin-3-yl)isoindoline-1,3-dione (4a) was inactivated. However, the inhibitory activities on TNF-α and IL-6 expression in HaCaT cells were improved by the substitution of a chloro-or methoxy-group at the phenyl position of 4a. The IL-6 inhibitory activity decreased in an order of 5c (69.44%) > 4c (48.73%) > 6c (3.19%) indicating the 3-substituted derivative is more active than the 4-substituted counterpart, which in turn is more active than the 2-substituted counterpart. Among them, 2-[1-(3-chlorobenzyl)-2,6-dioxopiperidin-3-yl]isoindoline-1,3-dione (5c) was found to inhibit TNF-α and IL-6 expression in HaCaT cells with a higher potency than thalidomide and no significant cell cytotoxicity was detected at 10 μM. In psoriasis, Compound 5c reduced IL-6, IL-8, IL-1β and IL-24 in imiquimod-stimulated models. Our results indicated that compound 5c is a potential lead of novel anti-psoriasis agents. Structural optimization of compound 5c and its in vivo assay are ongoing.
REGULATING CHIMERIC ANTIGEN RECEPTORS
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Page/Page column 297; 298; 299, (2018/09/08)
This invention is in the area of compositions and methods for regulating chimeric antigen receptor immune effector cell, for example T-cell (CAR-T), therapy to modulate associated adverse inflammatory responses, for example, cytokine release syndrome and tumor lysis syndrome, using targeted protein degradation.
TUNABLE ENDOGENOUS PROTEIN DEGRADATION WITH HETEROBIFUNCTIONAL COMPOUNDS
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Page/Page column 278-279; 280, (2018/09/08)
The present invention provides a means to modulate gene expression in vivo in a manner that avoids problems associated with CRISPR endogenous protein knock-out or knock-in strategies and strategies that provide for correction, or alteration, of single nucleotides. The invention includes inserting into the genome a nucleotide encoding a heterobifunctional compound targeting protein (dTAG) in-frame with the nucleotide sequence of a gene encoding an endogenously expressed protein of interest which, upon expression, produces an endogenous protein-dTAG hybrid protein. This allows for targeted protein degradation of the dTAG and the fused endogenous protein using a heterobifunctional compound.
