In modern organic synthesis, controlling molecular chirality is often just as important as constructing the molecular skeleton itself. For pharmaceutical intermediates, natural products, and other stereochemically complex molecules, the use of a reliable chiral starting material can simplify synthetic planning and improve stereochemical control.

Methyl D-lactate, also known as Methyl (R)-(+)-lactate, is one such chiral building block. With CAS No. 17392-83-5, this compound is the methyl ester of D-lactic acid and possesses a defined R configuration at its stereogenic center.

Its relatively simple molecular structure contains both a hydroxyl group and an ester group, while the existing stereocenter provides a useful source of chirality for subsequent synthetic transformations.

This combination makes Methyl D-lactate, (R)-Methyl lactate, and Methyl (R)-2-hydroxypropionate valuable terms not only in chemical procurement but also in the broader field of asymmetric synthesis.

Applications reported for this compound include its use as a starting material in the asymmetric preparation of Neomethymycin and PM-toxin A, as well as its use as a chiral-pool building block in stereoselective synthesis.

1. What Is Methyl D-Lactate?

Methyl D-lactate is the R-configured methyl ester of lactic acid.

Its principal chemical identifiers are:

PubChem identifies CAS 17392-83-5 as methyl (R)-2-hydroxypropanoate and lists C₄H₈O₃ as its molecular formula with a molecular weight of 104.10 g/mol.

SHLZ Pharma’s product information likewise identifies the material as Methyl (R)-(+)-lactate, CAS 17392-83-5, with C₄H₈O₃, molecular weight 104.1, boiling point 144–145 °C, and density of approximately 1.09 g/mL at 25 °C.

2. Why the R Configuration Matters

The most important feature distinguishing Methyl D-lactate from ordinary methyl lactate is not its molecular formula but its stereochemical configuration.

Methyl lactate contains a stereogenic carbon atom. Therefore, the compound exists as different enantiomeric forms.

Methyl (R)-(+)-lactate

and

Methyl (S)-(-)-lactate

have the same molecular formula and connectivity but different three-dimensional configurations.

For many synthetic applications, this distinction is critical.

A racemic methyl lactate mixture cannot automatically replace an enantiomerically defined starting material when a downstream synthesis requires a specific stereochemical configuration.

The R-configured structure of Methyl D-lactate can therefore serve as an initial source of stereochemical information in a synthetic sequence.

This is the fundamental reason that Methyl D-lactate is considered a chiral building block rather than simply another methyl ester.

3. Methyl D-Lactate as a Chiral-Pool Building Block

The term chiral pool refers to the use of readily available, enantiomerically defined natural or naturally derived compounds as starting materials for asymmetric synthesis.

Instead of creating every stereocenter through a separate asymmetric catalytic reaction, a chemist can begin with a molecule that already contains the required stereochemical information.

Methyl D-lactate is particularly suitable for this concept because it is:

Structurally simple

Enantiomerically defined

Functionalized with both hydroxyl and ester groups

Suitable for further chemical modification

Relatively compact for incorporation into larger synthetic structures

During a multistep synthesis, the existing stereocenter can become part of a more complex molecular framework.

This approach can reduce the need to establish chirality from scratch.

4. Functional Groups That Enable Further Synthesis

Methyl D-lactate contains two particularly useful functional groups:

Hydroxyl Group

The secondary alcohol provides a site for transformations such as activation, protection, oxidation, or other functional-group manipulations depending on the synthetic route.

Methyl Ester

The ester functionality can participate in a variety of transformations used to construct carbon-carbon or carbon-heteroatom bonds.

Together, these functional groups give Methyl D-lactate considerable synthetic flexibility.

More importantly, they are attached to a carbon framework that already contains a stereogenic center.

This combination of functionality + stereochemistry is what makes the molecule attractive for stereoselective synthesis.

5. Role in the Synthesis of Neomethymycin

One of the most notable applications associated with Methyl D-lactate is the asymmetric preparation of Neomethymycin.

Neomethymycin belongs to the methymycin family of macrolide antibiotics and contains a complex stereochemically defined molecular framework.

The construction of such natural products can involve multiple stereocenters and a macrocyclic structure.

For synthetic chemists, the challenge is not simply to connect the carbon atoms correctly. The stereochemical configuration of individual centers must also be controlled.

Methyl D-lactate can serve as a chiral starting material in this type of synthesis.

Its existing R-configured stereocenter provides an initial stereochemical element that can be carried into more advanced intermediates through appropriately designed synthetic transformations.

Public product information from Sigma-Aldrich specifically identifies (+)-Methyl D-lactate as a starting material for the asymmetric preparation of Neomethymycin.

This illustrates an important concept in organic synthesis:

A relatively small chiral molecule can provide stereochemical information for the construction of a much more complex natural product.

6. Application in PM-Toxin A Synthesis

Another reported application of Methyl D-lactate is its use as a starting material in the asymmetric preparation of PM-toxin A.

PM-toxin A belongs to a class of structurally complex natural products whose synthesis requires careful stereochemical control.

The use of a chiral-pool starting material such as Methyl D-lactate provides an alternative to generating every stereocenter independently through catalytic asymmetric reactions.

This can be especially useful when a target molecule contains multiple stereochemical elements.

Commercial chemical references and Sigma-Aldrich product documentation both identify Methyl D-lactate as a starting material for the asymmetric preparation of PM-toxin A.

7. From Simple Chiral Molecule to Complex Synthetic Target

The value of Methyl D-lactate becomes easier to understand when considering the progression of a typical synthetic strategy.

A simplified conceptual pathway can be represented as:

Methyl D-lactate

↓

Functional-group transformation

↓

Chiral intermediate

↓

Carbon-framework construction

↓

More advanced stereochemical intermediate

↓

Complex natural product or specialty molecule

The actual chemistry can involve many individual steps, and the exact pathway depends on the target compound.

However, the underlying principle remains the same:

the starting material contributes both chemical functionality and stereochemical information.

This dual role is one reason chiral building blocks remain important in modern organic synthesis.

8. Methyl (R)-Lactate vs. Racemic Methyl Lactate

A common issue during chemical procurement is the difference between an enantiomerically defined material and a racemic mixture.

Methyl D-lactate has a defined R configuration.

Its stereochemical identity can be represented by:

Methyl (2R)-2-hydroxypropanoate

The racemic form, by contrast, contains both enantiomers.

Although the molecular formula is the same, the two materials are not necessarily interchangeable in stereoselective synthesis.

For a synthetic route that relies on a specific stereochemical starting point, using an enantiomerically defined material can be essential.

Therefore, buyers should verify:

CAS number

Absolute configuration

Optical purity / enantiomeric excess

Assay

Analytical method

Batch consistency

This is particularly important when Methyl D-lactate is being used as a chiral-pool starting material.

9. Why Optical Purity Is an Important Specification

For ordinary chemical intermediates, assay may be the primary quality indicator.

For chiral compounds, however, chemical purity alone is not enough.

A material may have a high assay while still containing an undesired enantiomer.

For Methyl D-lactate, customers may therefore need to evaluate both:

Chemical purity

and

Enantiomeric purity

These two parameters answer different questions.

Chemical purity asks:

How much of the desired chemical compound is present?

Enantiomeric purity asks:

How much of the material has the desired stereochemical configuration?

For stereoselective synthesis, both can directly influence downstream results.

This is why analytical documentation and appropriate chiral analysis can be important when purchasing Methyl D-lactate for research or process development.

10. Physical and Chemical Characteristics

Methyl D-lactate is a relatively small organic ester and is reported as a clear, colorless liquid.

Its boiling point is approximately 144–145 °C, while its density is around 1.09 g/mL at 25 °C. The refractive index is approximately 1.413 at 20 °C.

Available supplier data also report an optical rotation in the positive direction, consistent with the R-configured material. Exact measured values can depend on concentration, temperature, and measurement conditions, so customers should refer to the applicable specification or certificate of analysis for a particular batch.

The compound is also reported as water miscible, with handling and storage requirements governed by the applicable SDS.

Because Methyl D-lactate is classified as a flammable liquid and can cause eye or respiratory irritation according to available safety information, appropriate laboratory or industrial handling procedures should be followed.

11. Beyond Natural Product Synthesis

The usefulness of Methyl D-lactate is not limited to Neomethymycin or PM-toxin A.

Its broader value comes from its role as a chiral synthetic building block.

Potential research and development applications include:

Chiral Intermediate Synthesis

Methyl D-lactate can be incorporated into synthetic routes requiring an existing stereocenter.

Asymmetric Organic Synthesis

It can serve as a starting point for constructing stereochemically defined molecules.

Natural Product Synthesis

Chiral-pool strategies are widely used when preparing complex natural products.

Pharmaceutical Chemistry

Defined stereochemical building blocks can be useful during the development of pharmaceutical intermediates and drug candidates.

Specialty Chemical Research

Its combination of hydroxyl, ester, and stereogenic functionality makes it useful for developing structurally diverse molecules.

The specific suitability of Methyl D-lactate should always be evaluated against the target synthesis and required product specifications.

12. What Should Buyers Look for in a Methyl D-Lactate Supplier?

For a chiral intermediate, supplier selection should go beyond price and nominal assay.

1. Confirm the Exact CAS Number

The target material is:

CAS No. 17392-83-5

This should be clearly stated on the quotation, specification, COA, and product documentation.

2. Confirm the Configuration

The requested compound is:

R / D configuration

rather than an unspecified or racemic methyl lactate.

3. Evaluate Optical Purity

For stereoselective applications, customers should confirm the available enantiomeric purity specification and analytical method.

4. Review Chemical Purity

Assay and impurity information should be evaluated according to the requirements of the downstream process.

5. Check Batch Consistency

For process development and commercial manufacturing, reproducibility between batches is critical.

6. Request Supporting Documentation

Depending on the application, buyers may request:

COA

SDS

Product specification

Analytical data

Packaging information

Batch information

A supplier capable of providing clear and consistent documentation can significantly simplify qualification.

13. SHLZ Pharma: Supplying Methyl (R)-(+)-Lactate

SHLZ Pharma supplies Methyl (R)-(+)-lactate CAS No. 17392-83-5 as part of its portfolio of pharmaceutical intermediates, chiral compounds, and specialty chemical building blocks.

According to the company’s product information, Methyl (R)-(+)-lactate is a regularly produced product, with supply available for both smaller samples and larger-volume requirements.

For customers using the compound in stereoselective synthesis, the focus should be on more than simply supplying the chemical name.

A reliable supply program should combine:

Product Identity

Clear identification of CAS No. 17392-83-5 and the R configuration.

Quality Control

Appropriate analytical testing to monitor chemical quality and, where required, stereochemical purity.

Flexible Supply

Support for laboratory evaluation, process development, and larger-scale purchasing.

Technical Documentation

Clear specifications and batch-related analytical documentation.

International Service

Professional communication and logistics support for customers conducting chemical and pharmaceutical development internationally.

14. Why Chiral Building Blocks Remain Important

As synthetic targets become more structurally complex, stereochemical control continues to be a central consideration in organic chemistry.

There are several ways to introduce chirality into a molecule, including:

Asymmetric catalysis

Chiral auxiliaries

Resolution

Enzymatic methods

Chiral-pool synthesis

Chiral-pool synthesis remains attractive because it starts from a molecule whose stereochemistry is already established.

Methyl D-lactate represents a particularly compact example of this strategy.

Rather than creating a stereocenter later in the synthesis, chemists can incorporate an existing stereochemical element at an early stage and build upon it.

This can be strategically valuable when designing multistep routes toward complex molecules.

15. Frequently Asked Questions

What is the CAS number of Methyl D-lactate?

The CAS number of Methyl D-lactate / Methyl (R)-(+)-lactate is 17392-83-5.

What is another name for Methyl D-lactate?

Common names include Methyl (R)-(+)-lactate, (R)-Methyl lactate, D-lactic acid methyl ester, and Methyl (R)-2-hydroxypropionate.

What is the molecular formula of Methyl D-lactate?

Its molecular formula is C₄H₈O₃, and its molecular weight is approximately 104.10 g/mol.

Is Methyl D-lactate a chiral compound?

Yes. Methyl D-lactate has a defined R configuration and is the enantiomer of methyl (S)-lactate.

What is Methyl D-lactate used for?

It can be used as a chiral building block and chiral-pool starting material in stereoselective synthesis. Reported applications include asymmetric preparation of Neomethymycin and PM-toxin A.

Why is optical purity important for Methyl D-lactate?

Because its value in stereoselective synthesis comes partly from its defined R configuration. The presence of the opposite enantiomer can affect a downstream synthesis that depends on stereochemical purity.

What should I confirm before purchasing Methyl D-lactate?

Buyers should confirm the CAS number, R/D configuration, chemical purity, enantiomeric purity, analytical method, batch consistency, COA, and SDS before using the material in a stereoselective process.

Conclusion

Methyl D-lactate, also known as Methyl (R)-(+)-lactate, (R)-Methyl lactate, and Methyl (R)-2-hydroxypropionate, is a compact but valuable chiral building block with CAS No. 17392-83-5.

Its molecular formula is C₄H₈O₃, with a molecular weight of approximately 104.10 g/mol. The molecule combines a secondary hydroxyl group, a methyl ester, and a defined R-configured stereocenter, providing both chemical functionality and stereochemical information for subsequent synthesis.

Its reported use as a starting material in the asymmetric preparation of Neomethymycin and PM-toxin A demonstrates the practical value of Methyl D-lactate in complex stereoselective synthesis. It can also serve as a chiral-pool building block in broader asymmetric organic chemistry.

For pharmaceutical and specialty chemical manufacturers, the key consideration is therefore not simply whether a supplier can provide “methyl lactate,” but whether the supplier can consistently provide the correct stereochemical form, chemical quality, analytical documentation, and reliable batch-to-batch supply.

SHLZ Pharma provides Methyl (R)-(+)-lactate CAS No. 17392-83-5 for customers seeking a reliable chiral intermediate and synthetic building block for research, process development, and specialty chemical applications.