L-glufosinate

Introduction

Given the current challenges with — in some countries bans of — Glyphosate, Glufosinate has become a possible candidate to replace the widespread usage of Glyphosate in agriculture. Glufosinate, however, is long plagued by three major issues — the high cost (roughly 2x-3x over Glyphosate), high environmental impact, and relatively small selection of Glufosinate-resistant seeds. L-glufosinate is the next generation, more environmentally friendly replacement of Glufosinate. But manufacturing L-glufosinate at a low cost and with scale is still a challenge. Currently, manufacturers synthesize L-glufosinate primarily in two ways: through asymmetric chemical synthesis and relying on biochemical processes. Both methods have serious constraints on volume and cost.

To improve the market competitiveness of Glufosinate, Vulpes developed an entirely new manufacturing process for L-glufosinate, to reduce Glufosinate’s environmental impact, reduce its cost, and potentially better place Glufosinate as a possible candidate to replace Glyphosate. Vulpes’s innovation is possible because Vulpes’s team has 20 years of history working on chiral amino acids and their derivatives. For example, its technology on chiral Aminobutyric acids and their derivatives upset the global market of Levetiracetam, an anti-seizure drug. 20 years later, Vulpes’s team’s innovation is still the main manufacturing approach for Levetiracetam.

The Competition

Current manufacturers of L-glufosinate all suffer from high costs and challenges in industrialization.

Method 1

Method 1 uses L-Glutamic acid as the source material. It protects the amino acid structure first, and then relies on elimination reaction to arrive at amino acid protected derivatives of L-2-Amino-3-butenoic acid. The process requires protecting the amino acid and then removing the protection. The process, coupled with elimination reaction, has a very low yield and hence pushes up the cost.

Figure 1: Chemical Synthesis of L-glufosinate, Method 1

Method 2

Method 2 uses L-Glutamic acid or L-Aspartic acid as chiral source material. The method requires a long set of steps, which leads to significant challenges in manufacturing and is difficult to scale up and provide the volume needed by the market.

Figure 2: Chemical Synthesis of L-glufosinate, Method 2

Method 3

Method 3 relies on L-Methionine as the source material. In the manufacturing process leading up to Chemical V, the use of sulfoxides and Lewis acids such as Zinc chloride increases the manufacturing cost and the environmental impact. Because of very complicated post-processing steps after the reaction, the method is not suitable for large-scale industrialization. The massive usage of ​Methyldiethoxyphosphine makes the reaction potentially dangerous. The recycling of ​Methyldiethoxyphosphine is challenging and costly. Lastly, L-Methionine is expensive and may lead to a lot of sulfur-containing wastes.

Figure 3: Chemical Synthesis of L-glufosinate, Method 3

Method 4

Method 4 uses L-Homoserine to manufacture L-glufosinate. Although the manufacturing process is fairly simple, L-Homoserine is quite expensive. Further, the use of enzymes requires very demanding reaction conditions, further increasing the cost.

Figure 4: Chemical Synthesis of L-glufosinate, Method 4

Vulpes’s Advantage

Unlike major competitors on the market, Vulpes’s novel process thinks out of the box. For the chirality of L-glufosinate, existing manufacturing processes often rely on either asymmetric synthesis or enzyme-based methods. Asymmetric synthesis greatly limits the industrial capacity and some methods use cyanide catalysts and enzyme-based synthesis has a lot of waste. In short, all existing processes are expensive, and most more expensive than Glufosinate.

Vulpes’s novel process avoid all the aforementioned problems and is massively cheaper than existing processes.

 CostManufacturing DifficultyWasteDanger
Vulpes MethodLowLowLowLow
Method 1HighMediumLowLow
Method 2HighHighLowLow
Method 3HighHighHighHigh
Method 4HighHighHighLow
Table 1: Technological Comparison

With the novel process, Vulpes has achieved the following:

  • No enzyme or fermentation involved
  • High Enantiomeric Excess
  • Environment-friendly and simple process
  • Globally competitive cost

If you are interested in procuring the products or seeking partnership, please contact us at rick@vulpescorp.com or at (314) 833-8683